feat(api): add public status endpoints with version injection

Replace health_handler with status_handler providing public /status and
/about endpoints. Add build-time version injection via ldflags in
Makefile, and support --version/-v CLI flag.

- Add /status endpoint returning runtime status, uptime, and version
- Add /about endpoint with system metadata (name, description, repo)
- Configure VERSION variable with git describe fallback
- Update swagger docs and api.md for new public endpoints
- Remove deprecated /api/status/test endpoint

docs/swagger.yaml

@@ -247,17 +247,6 @@ definitions:
       updatedAt:
         type: string
     type: object
-  github_com_ez-api_ez-api_internal_service.HealthStatus:
-    properties:
-      database:
-        type: string
-      redis:
-        type: string
-      status:
-        type: string
-      uptime:
-        type: string
-    type: object
   github_com_ez-api_ez-api_internal_service.LogWebhookConfig:
     properties:
       cooldown_seconds:
@@ -328,6 +317,21 @@ definitions:
         description: Valid is true if Time is not NULL
         type: boolean
     type: object
+  internal_api.AboutResponse:
+    properties:
+      description:
+        example: High-performance LLM API gateway
+        type: string
+      name:
+        example: EZ-API Gateway
+        type: string
+      repository:
+        example: https://github.com/ez-api/ez-api
+        type: string
+      version:
+        example: 0.1.0
+        type: string
+    type: object
   internal_api.AccessResponse:
     properties:
       default_namespace:
@@ -712,6 +716,18 @@ definitions:
       tokens:
         type: integer
     type: object
+  internal_api.StatusResponse:
+    properties:
+      status:
+        example: ok
+        type: string
+      uptime:
+        example: 72h30m15s
+        type: string
+      version:
+        example: 0.1.0
+        type: string
+    type: object
   internal_api.TokenView:
     properties:
       allow_ips:
@@ -943,6 +959,19 @@ info:
   title: EZ-API Control Plane
   version: 0.0.1
 paths:
+  /about:
+    get:
+      description: Returns system metadata for display on an about page
+      produces:
+      - application/json
+      responses:
+        "200":
+          description: OK
+          schema:
+            $ref: '#/definitions/internal_api.AboutResponse'
+      summary: Get system information
+      tags:
+      - Public
   /admin/api-keys:
     get:
       description: List API keys
@@ -2744,23 +2773,6 @@ paths:
       summary: Force sync snapshot
       tags:
       - admin
-  /api/status/test:
-    get:
-      description: Checks Redis/PostgreSQL connections and reports status
-      produces:
-      - application/json
-      responses:
-        "200":
-          description: OK
-          schema:
-            $ref: '#/definitions/github_com_ez-api_ez-api_internal_service.HealthStatus'
-        "503":
-          description: Service Unavailable
-          schema:
-            $ref: '#/definitions/github_com_ez-api_ez-api_internal_service.HealthStatus'
-      summary: Test dependency connectivity
-      tags:
-      - system
   /auth/whoami:
     get:
       description: |-
@@ -2845,6 +2857,19 @@ paths:
       summary: Ingest logs
       tags:
       - system
+  /status:
+    get:
+      description: Returns public runtime status information without sensitive data
+      produces:
+      - application/json
+      responses:
+        "200":
+          description: OK
+          schema:
+            $ref: '#/definitions/internal_api.StatusResponse'
+      summary: Get system status
+      tags:
+      - Public
   /v1/logs:
     get:
       description: List request logs for the authenticated master