...d reasoning wrapping improvements
Summary:
1. Added `gpt-5.3-codex` model support across routing and exposed reasoning model variants.
2. Added dynamic Copilot tool discovery to support GitHub Copilot Ollama provider without hardcoded tool lists.
3. Enabled default Copilot tools and MCP tools by parsing tool declarations from system instructions and inferring schemas from history.
4. Improved reasoning compatibility handling for Copilot Ollama flows and wrapped thinking output more reliably.
5. Updated documentation for model support and tool/reasoning behavior.
6. Total: 6 files changed, +1170 / -174 lines.
Features:
1. GPT-5.3 Codex: Added model recognition and reasoning-variant exposure for `gpt-5.3-codex`.
2. Dynamic Tool Discovery: Introduced runtime derivation of tool schemas from Copilot system instructions (`type ... = (_: {...}) => any;`) and historical function calls.
3. Copilot Ollama Compatibility: Added fallback path for requests that omit `tools`, preserving function-calling behavior with BYOK/OpenAI-compatible payloads.
4. Tool Passthrough Safety: Improved handling of `responses_tools` and tool-choice behavior for mixed client compatibility.
5. Reasoning Compatibility: Applied Copilot-specific reasoning compatibility mode to avoid conflicting `<think>` behavior in Copilot surfaces.
Changes:
1. Modified `chatmock/utils.py` (+651/-?):
 - Added `extract_copilot_tools_from_system_instructions`.
 - Added `infer_tools_from_chat_history`.
 - Added `derive_copilot_tools_dynamically`.
 - Improved SSE translation behavior around tool-call emission and stop-chunk handling.
2. Modified `chatmock/routes_openai.py` (+241/-?):
 - Added `gpt-5.3-codex` handling.
 - Added Copilot Ollama request detection and dynamic tool-derivation fallback.
 - Applied Copilot-specific reasoning compatibility in response shaping.
 - Updated exposed reasoning model variants list.
3. Modified `chatmock/routes_ollama.py` (+352/-?):
 - Added Ollama-provider compatibility refinements for Copilot request/response behavior.
4. Modified `chatmock/reasoning.py` (+15/-?):
 - Minor reasoning behavior alignment for compatibility flow.
5. Modified `chatmock/upstream.py` (+39/-?):
 - Upstream request/compatibility adjustments for new tool/reasoning pathways.
6. Modified `README.md` (+46/-?):
 - Documented `gpt-5.3-codex` support.
 - Clarified tool-calling and reasoning/thinking options.
Bug Fixes:
1. Fixed Copilot Ollama sessions where missing `tools` in request body caused degraded/non-functional function calling.
2. Fixed instruction/tool-schema conflicts by avoiding incompatible static instruction overlays in Copilot Ollama paths.
3. Improved reliability of thinking wrapper output in SSE translation flow.
Tests:
1. Verified modified files via `git status` and `git diff`.
2. Validated change scope with `git diff --stat` (6 files, +1170 / -174).
3. Manual flow validation targeted for Copilot Ollama + tool calling + reasoning compatibility paths.
Task: ChatMock Copilot Ollama compatibility + GPT-5.3-codex enablement
Signed-off-by: Punal Manalan <punal100@gmail.com>