Add scout MCP server for browser recon + msgspec workspace dep

- tools/scout/: browser automation MCP server using Pydoll (CDP, no WebDriver)
  - scout_visit, scout_elements (text-first), scout_click, scout_fill, scout_select
  - scout_scroll, scout_text, scout_screenshot (opt-in)
  - scout_har_start / scout_har_stop (asyncio task holds recording context open)
  - scout_analyze: HAR parsing with HarEntry/HarSummary msgspec structs
  - Standalone project (not workspace member — websockets conflict with prefect)
  - Runs via: uv run --directory tools/scout scout-server

- .mcp.json: registers scout as Claude Code MCP server (project scope)

- msgspec>=0.19 added to root project deps (workspace-wide struct/validation)

- coding_philosophy.md: document msgspec as approved dep, usage rules

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

tools/scout/pyproject.toml

@@ -0,0 +1,20 @@
+[project]
+name = "scout"
+version = "0.1.0"
+description = "Browser recon MCP server — discover API endpoints via HAR recording"
+requires-python = ">=3.13"
+dependencies = [
+    "pydoll-python>=1.5",
+    "mcp[cli]>=1.0",
+    "msgspec>=0.19",
+]
+
+[project.scripts]
+scout-server = "scout.server:main"
+
+[build-system]
+requires = ["hatchling"]
+build-backend = "hatchling.build"
+
+[tool.hatch.build.targets.wheel]
+packages = ["src/scout"]