feat(cpp): merge gaia-bash native binary template (PR #985)

[kovtcharov-amd]

PR #985 adds 8,569 LOC establishing the template for native C++ agent binaries with 5 interfaces (TUI, CLI, pipe, REST API, MCP stdio). This is the foundation for any future C++ agent binary.

Adds to framework:

• ProcessRunner, FileIOTools, GitTools, SessionStore
• TuiConsole (FTXUI-based rich TUI)
• REST API server (OpenAI-compatible `/v1/chat/completions`)
• MCP stdio server (`tools/list` + `tools/call`)
• BashAgent as reference implementation

Tasks

• Review and merge PR feat(cpp): gaia-bash — native C++ bash coding agent with TUI, API server, MCP server #985 (431/435 tests pass, 4 pre-existing)
• Validate all 5 interfaces end-to-end
• Document the binary template pattern for new agent creation

Ref: PR #985

[github-actions]

PR #985 isn't ready to merge yet — the C++ Build & Test workflow is currently red on both Linux and Windows on the latest run (2026-05-14, run 25876448781), and there are no reviews on the PR. Sequencing the tasks below against current state:

🟡 Task 1 — Review & merge PR #985 (blocked)

CI blockers on main-merge-target HEAD:

• 🔴 C++ Install Test (ubuntu-latest, windows-latest) — CMake Error at CMakeLists.txt:24 (find_package): The following imported targets are referenced, but are missing: — install/export config appears to reference a target that isn't being exported by the build tree.
• 🔴 C++ (ubuntu-latest, windows-latest) — fails at ctest stage; the WiFi test failures (WiFiToolsTest.PingHostMissingArgReturnsError etc.) appear pre-existing (matching the "4 pre-existing failures" called out in the PR body), but the workflow as a whole is failing.
• 🔴 C++ Shared Library (windows-latest) and C++ Integration Tests (STX) — both red.
• 🟡 No reviews — 8,569 LOC across 40 files needs at least one human reviewer; consider splitting threads (M1 framework upgrades / M2 BashAgent / API+MCP server / eval scenarios) into stacked PRs to make review tractable.

🟢 Task 2 — Validate 5 interfaces end-to-end

The PR body marks TUI / /v1/chat/completions / eval scenarios as still pending (they need a running Lemonade Server). That's the right gate after CI is green — file a follow-up tracking checklist once the merge blockers above clear.

🟢 Task 3 — Document the binary template pattern

Once merged, the binary-template docs should land under docs/sdk/ (likely a new docs/sdk/cpp/ section) and be linked from docs/docs.json. Per CLAUDE.md, this is required for the feature work itself — worth queueing as a follow-up PR rather than bundling more into #985.

Suggested next step: ask @kovtcharov-amd whether to (a) push the CMake-export fix to #985 and re-run, or (b) split the PR into stacked smaller ones to make review feasible. The merge gate isn't a single approval — it's CI-green + reviewer sign-off, neither of which exist yet.

[kovtcharov-amd]

Closing as completed. PR #985 (gaia-bash — native C++ bash coding agent with TUI, API server, and MCP server) is merged on main. The merge this issue tracked is done.