feat: support PascalCase local-name drift in DSML tool markup parsing

Detect camelCase→PascalCase boundaries between arbitrary prefixes and fixed
local names (tool_calls/invoke/parameter), so that fused forms like
<DSmartToolCalls> are recognized without explicit separator characters.
Also add the underscore-free alias "toolcalls" as a valid DSML local name.
Includes lookalike rejection tests to ensure near-matches like
<DSmartToolCallsExtra> are not falsely accepted.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

API.en.md

@@ -40,7 +40,7 @@ Docs: [Overview](README.en.md) / [Architecture](docs/ARCHITECTURE.en.md) / [Depl
 
 - OpenAI / Claude / Gemini protocols are now mounted on one shared `chi` router tree assembled in `internal/server/router.go`.
 - Adapter responsibilities are streamlined to: **request normalization → DeepSeek invocation → protocol-shaped rendering**, reducing legacy split-logic paths.
-- Tool-calling semantics are aligned between Go and Node runtime: models should output the fullwidth-separator DSML shell `<｜DSML｜tool_calls>` → `<｜DSML｜invoke name="...">` → `<｜DSML｜parameter name="...">`; DS2API also accepts the halfwidth DSML wrapper `<|DSML|tool_calls>`, DSML wrapper aliases such as `<dsml|tool_calls>`, `<|tool_calls>`, `<｜tool_calls>`, common DSML separator drift such as `<|DSML tool_calls>`, collapsed DSML local names such as `<DSMLtool_calls>`, control-separator drift such as `<DSML␂tool_calls>` / raw STX `\x02`, CJK angle bracket, fullwidth-bang / ideographic-comma separator drift, and trailing attribute separator drift such as `<DSM｜parameter name="command"｜>...〈/DSM｜parameter〉`, `<！DSML！invoke name=“Bash”>`, `<、DSML、tool_calls>`, or `<DSMLtool_calls※>`, arbitrary protocol prefixes such as `<proto💥tool_calls>`, and legacy canonical XML `<tool_calls>` → `<invoke name="...">` → `<parameter name="...">`. The scanner normalizes fixed local names (`tool_calls` / `invoke` / `parameter`) with non-structural separators before or after them back to XML before parsing, and also tolerates CDATA opener drift such as `<！[CDATA[` / `<、[CDATA[`; only wrapped tool blocks or the narrow missing-opening-wrapper repair path enter the tool path, while bare `<invoke>` does not count as supported syntax. JSON literal parameter bodies are preserved as structured values, explicit empty or whitespace-only parameters are preserved as empty strings, malformed complete wrappers are released as plain text, and loose CDATA is narrowly repaired at final parse/flush when it can preserve a complete outer tool call.
+- Tool-calling semantics are aligned between Go and Node runtime: models should output the fullwidth-separator DSML shell `<｜DSML｜tool_calls>` → `<｜DSML｜invoke name="...">` → `<｜DSML｜parameter name="...">`; DS2API also accepts the halfwidth DSML wrapper `<|DSML|tool_calls>`, DSML wrapper aliases such as `<dsml|tool_calls>`, `<|tool_calls>`, `<｜tool_calls>`, common DSML separator drift such as `<|DSML tool_calls>`, collapsed DSML local names such as `<DSMLtool_calls>`, control-separator drift such as `<DSML␂tool_calls>` / raw STX `\x02`, CJK angle bracket, fullwidth-bang / ideographic-comma separator drift, PascalCase local-name drift, and trailing attribute separator drift such as `<DSM｜parameter name="command"｜>...〈/DSM｜parameter〉`, `<！DSML！invoke name=“Bash”>`, `<、DSML、tool_calls>`, `<DSmartToolCalls>`, or `<DSMLtool_calls※>`, arbitrary protocol prefixes such as `<proto💥tool_calls>`, and legacy canonical XML `<tool_calls>` → `<invoke name="...">` → `<parameter name="...">`. The scanner normalizes fixed local names (`tool_calls` / `invoke` / `parameter`) with non-structural separators before or after them back to XML before parsing, and also tolerates CDATA opener drift such as `<！[CDATA[` / `<、[CDATA[`; only wrapped tool blocks or the narrow missing-opening-wrapper repair path enter the tool path, while bare `<invoke>` does not count as supported syntax. JSON literal parameter bodies are preserved as structured values, explicit empty or whitespace-only parameters are preserved as empty strings, malformed complete wrappers are released as plain text, and loose CDATA is narrowly repaired at final parse/flush when it can preserve a complete outer tool call.
 - `Admin API` separates static config from runtime policy: `/admin/config*` for configuration state, `/admin/settings*` for runtime behavior.
 - When upstream returns a thinking-only response with no visible text, the Go main path for both streaming and non-streaming completions retries once in the same DeepSeek session: it appends the prompt suffix `"Previous reply had no visible output. Please regenerate the visible final answer or tool call now."` and sets `parent_message_id`. If that same-account retry would still end as `429 upstream_empty_output`, managed-account mode switches to the next available account, creates a fresh session, and retries the original payload once before returning 429.
 - Citation/reference marker boundary: streaming output hides upstream `[citation:N]` / `[reference:N]` placeholders by default; non-stream output converts DeepSeek search reference markers into Markdown links.
@@ -355,7 +355,7 @@ When `tools` is present, DS2API performs anti-leak handling:
 
 Additional notes:
 
-- The parser treats the recommended DSML shell tool blocks (`<｜DSML｜tool_calls>` / `<｜DSML｜invoke name="...">` / `<｜DSML｜parameter name="...">`), halfwidth DSML shell blocks (`<|DSML|tool_calls>` / `<|DSML|invoke name="...">` / `<|DSML|parameter name="...">`), DSML wrapper aliases (`<dsml|tool_calls>`, `<|tool_calls>`, `<｜tool_calls>`), common DSML separator drift (`<|DSML tool_calls>` / `<|DSML invoke>` / `<|DSML parameter>`), collapsed DSML local names (`<DSMLtool_calls>` / `<DSMLinvoke>` / `<DSMLparameter>`), control-separator drift (`<DSML␂tool_calls>` / raw STX `\x02`), CJK angle bracket, fullwidth-bang / ideographic-comma separator drift, and trailing attribute separator drift (`<DSM｜parameter name="command"｜>...〈/DSM｜parameter〉` / `<！DSML！invoke name=“Bash”>` / `<、DSML、tool_calls>` / `<DSMLtool_calls※>`), arbitrary protocol prefixes (`<proto💥tool_calls>`), and legacy canonical XML tool blocks (`<tool_calls>` / `<invoke name="...">` / `<parameter name="...">`) as executable tool calls. These shells normalize non-structural separators back to XML first, while internal parsing remains XML-based; CDATA opener drift such as `<！[CDATA[` / `<、[CDATA[` is also normalized for parameter bodies. Legacy `<tools>`, `<tool_call>`, `<tool_name>`, `<param>`, `<function_call>`, `tool_use`, antml variants, and standalone JSON `tool_calls` payloads are treated as plain text; complete but malformed wrappers are also released as plain text.
+- The parser treats the recommended DSML shell tool blocks (`<｜DSML｜tool_calls>` / `<｜DSML｜invoke name="...">` / `<｜DSML｜parameter name="...">`), halfwidth DSML shell blocks (`<|DSML|tool_calls>` / `<|DSML|invoke name="...">` / `<|DSML|parameter name="...">`), DSML wrapper aliases (`<dsml|tool_calls>`, `<|tool_calls>`, `<｜tool_calls>`), common DSML separator drift (`<|DSML tool_calls>` / `<|DSML invoke>` / `<|DSML parameter>`), collapsed DSML local names (`<DSMLtool_calls>` / `<DSMLinvoke>` / `<DSMLparameter>`), control-separator drift (`<DSML␂tool_calls>` / raw STX `\x02`), CJK angle bracket, fullwidth-bang / ideographic-comma separator drift, PascalCase local-name drift, and trailing attribute separator drift (`<DSM｜parameter name="command"｜>...〈/DSM｜parameter〉` / `<！DSML！invoke name=“Bash”>` / `<、DSML、tool_calls>` / `<DSmartToolCalls>` / `<DSMLtool_calls※>`), arbitrary protocol prefixes (`<proto💥tool_calls>`), and legacy canonical XML tool blocks (`<tool_calls>` / `<invoke name="...">` / `<parameter name="...">`) as executable tool calls. These shells normalize non-structural separators back to XML first, while internal parsing remains XML-based; CDATA opener drift such as `<！[CDATA[` / `<、[CDATA[` is also normalized for parameter bodies. Legacy `<tools>`, `<tool_call>`, `<tool_name>`, `<param>`, `<function_call>`, `tool_use`, antml variants, and standalone JSON `tool_calls` payloads are treated as plain text; complete but malformed wrappers are also released as plain text.
 - The parser no longer drops tool calls solely because parameter values are empty; explicit empty strings or whitespace-only parameters become empty strings in structured `tool_calls`. Prompting still tells the model not to emit blank parameters, and missing/empty argument rejection belongs in the tool executor or client schema validation.
 - If the final visible response text is empty but the reasoning stream contains an executable tool call, Chat / Responses emits a standard OpenAI `tool_calls` / `function_call` output during finalization. If thinking/reasoning was not enabled by the client, that reasoning text is used only for detection and is not exposed as visible text or `reasoning_content`.
 - `tool_calls` shown inside fenced markdown code blocks (for example, ```json ... ```) are treated as examples, not executable calls.