feat: endpoint-centric API map UI (GLA-48)

[paoloanzn]

Summary

• Replace request-centric list+detail view with an endpoint-centric API map that reads like an API reference
• One row per unique endpoint (method + normalized URL + observation count), sorted by max relevance score
• Detail pane shows merged schemas: auth headers with badges, request/response header tables, and body schemas rendered as indented type trees
• All existing functionality preserved (snapshot/live toggle, cookie capture, JSON export)

Test plan

• Open DevTools panel and trigger network activity — verify endpoints appear as grouped rows (not individual requests)
• Click an endpoint row — verify detail pane shows Authentication, Request Headers, Request Body, Response Headers, Response Body sections
• Trigger multiple requests to the same endpoint — verify observation count increments and schemas merge correctly
• Verify auth headers (Authorization, Cookie, x-api-key, etc.) show 🔑 icon in list and AUTH badge in detail
• Take a snapshot — verify cookies still capture and export JSON includes endpoint summaries
• Test responsive layout at narrow widths

🤖 Generated with Claude Code

[linear]

GLA-48 Map UI

Replace the current request list with an endpoint-centric view of the map.

• One row per unique endpoint (method + normalized URL + observation count)
• Expand an endpoint to see: auth headers, request schema, response schema
• Live updates as new observations come in

Done when the panel reads like an API reference, not a request log.