feat(windsurf): add Windsurf (Codeium) integration via MCP

[DK09876]

Summary

Adds a first-party Windsurf (Codeium) integration: a config-only CLI (hindsight-windsurf) that gives Cascade persistent long-term memory through the Hindsight MCP server — mirroring the MCP-convergence pattern of the Zed / Continue / OpenHands / GitHub Copilot integrations.

hindsight-windsurf init:

• Wires the Hindsight MCP server into Windsurf's global ~/.codeium/windsurf/mcp_config.json under mcpServers as a remote server (serverUrl + optional Authorization: Bearer header — Windsurf connects to the HTTP endpoint directly, no bridge).
• Writes an always-on recall/retain rule to .windsurf/rules/hindsight.md (trigger: always_on frontmatter), a dedicated sentinel-marked file so update/uninstall never touch the user's other rules.

Both config formats were verified against Windsurf's current live docs.

Package (hindsight_windsurf)

• config.py — layered defaults → ~/.hindsight/windsurf.json → env (HINDSIGHT_WINDSURF_BANK_ID), bank defaults to windsurf
• mcp_config.py — mcpServers.hindsight writer; strict-JSON parse-or-print fallback (never rewrites a file it can't round-trip)
• rules.py — dedicated .windsurf/rules/hindsight.md with always_on frontmatter
• cli.py — init / status / uninstall (+ --print-only)

Meets the merge checklist

• Tests exercise the framework — 25 unit tests (config / mcp_config / rules / cli) + a gated live-MCP-endpoint E2E (requires_real_llm)
• CI job — test-windsurf-integration added to test.yml (detect-changes filter, output decl, aggregation list)
• Release registration — added to release-integration.sh VALID_INTEGRATIONS and generate_changelog.py INTEGRATIONS
• Docs / registry — integrations.json entry (strict JSON; check-integrations.mjs passes), docs-integrations/windsurf.md, icon, README row

Validation

• pytest -m 'not requires_real_llm' → 25 passed; ruff (repo-root config) clean; uv build + uv.lock committed
• Real-app smoke against a local Hindsight: init wrote the correct mcp_config.json + always_on rule file, and a live MCP handshake (initialize → tools/list → recall) against that exact endpoint returned all seeded facts — same validation depth as Zed/OpenCode.

🤖 Generated with Claude Code