fix: move 5 path-param endpoints to query params for Vercel routing (#472)

Vercel's `api/[domain]/v1/[rpc].ts` captures one dynamic segment.
Path params like `/get-humanitarian-summary/SA` add an extra segment
that has no matching route file, causing 404 on both OPTIONS preflight
and direct requests. These endpoints were broken in production.

Changes:
- Remove `{param}` from 5 service.proto HTTP paths
- Add `(sebuf.http.query)` annotations to request message fields
- Update generated client/server code to use URLSearchParams
- Update OpenAPI specs (YAML + JSON) to declare query params
- Add early-return guards in 4 handlers for missing required params
- Add happy.worldmonitor.app to runtime.ts redirect hosts

Affected endpoints:
- GET /api/conflict/v1/get-humanitarian-summary?country_code=SA
- GET /api/economic/v1/get-fred-series?series_id=T10Y2Y&limit=120
- GET /api/market/v1/get-country-stock-index?country_code=US
- GET /api/intelligence/v1/get-country-intel-brief?country_code=US
- GET /api/military/v1/get-aircraft-details?icao24=a12345

docs/api/MarketService.openapi.yaml

@@ -194,7 +194,7 @@ paths:
                         application/json:
                             schema:
                                 $ref: '#/components/schemas/Error'
-    /api/market/v1/get-country-stock-index/{country_code}:
+    /api/market/v1/get-country-stock-index:
         get:
             tags:
                 - MarketService
@@ -203,7 +203,7 @@ paths:
             operationId: GetCountryStockIndex
             parameters:
                 - name: country_code
-                  in: path
+                  in: query
                   description: ISO 3166-1 alpha-2 country code (e.g., "US", "GB", "JP").
                   required: true
                   schema: