feat(web,server): expose server version and commit hash in Profile page

Add version and commit_hash fields to the /ping endpoint response,
sourced from the existing internal/version package (ldflags or
Go build info). The frontend capabilities store reads these values
and displays them as badges at the bottom of the Profile page.

spec/docs.go

@@ -10960,6 +10960,9 @@ const docTemplate = `{
         "handlers.PingResponse": {
             "type": "object",
             "properties": {
+                "commit_hash": {
+                    "type": "string"
+                },
                 "container_backend": {
                     "type": "string"
                 },
@@ -10968,6 +10971,9 @@ const docTemplate = `{
                 },
                 "status": {
                     "type": "string"
+                },
+                "version": {
+                    "type": "string"
                 }
             }
         },

spec/swagger.json

@@ -10951,6 +10951,9 @@
         "handlers.PingResponse": {
             "type": "object",
             "properties": {
+                "commit_hash": {
+                    "type": "string"
+                },
                 "container_backend": {
                     "type": "string"
                 },
@@ -10959,6 +10962,9 @@
                 },
                 "status": {
                     "type": "string"
+                },
+                "version": {
+                    "type": "string"
                 }
             }
         },

spec/swagger.yaml

@@ -1445,12 +1445,16 @@ definitions:
     type: object
   handlers.PingResponse:
     properties:
+      commit_hash:
+        type: string
       container_backend:
         type: string
       snapshot_supported:
         type: boolean
       status:
         type: string
+      version:
+        type: string
     type: object
   handlers.ProbeResponse:
     properties: