perf(panel): speed up file browsing and preserve loading forms

docs/openapi.yaml

@@ -1625,6 +1625,56 @@ paths:
         '404':
           $ref: '#/components/responses/NotFound'
 
+  /api/v1/internal/file-browser/{id}:
+    post:
+      tags: [files]
+      operationId: internalFileBrowser
+      summary: Exchange a read-only file Job's result for its next command.
+      description: >-
+        Internal face only. A random bearer token scopes the worker to one
+        world and a four-minute session; idle workers exit after 45 seconds.
+        The first request sends an empty object. Later requests return the
+        previous command's id and result or error. This endpoint dispatches
+        only reads already authorized by the external file API.
+      x-felis-face: [internal]
+      x-felis-tier: public
+      security: []
+      parameters:
+        - { name: id, in: path, required: true, schema: { type: string } }
+        - { name: Authorization, in: header, required: true, schema: { type: string } }
+      requestBody:
+        required: true
+        content:
+          application/json:
+            schema:
+              type: object
+              properties:
+                id: { type: string }
+                result: { type: object }
+                error: { type: string }
+      responses:
+        '200':
+          description: The next authorized read command.
+          content:
+            application/json:
+              schema:
+                type: object
+                required: [id, op, path]
+                properties:
+                  id: { type: string }
+                  op: { type: string, enum: [list, read] }
+                  path: { type: string }
+        '204':
+          $ref: '#/components/responses/NoContent'
+        '400':
+          $ref: '#/components/responses/BadRequest'
+        '404':
+          $ref: '#/components/responses/NotFound'
+        '409':
+          $ref: '#/components/responses/Conflict'
+        '503':
+          $ref: '#/components/responses/ServiceUnavailable'
+
   /api/v1/internal/exports/{id}:
     put:
       tags: [backups]

docs/troubleshooting.md

@@ -3170,8 +3170,18 @@ for 10 seconds (the Free plan's limits).
 ## 18. Server files: a change or an upload is refused
 
 The panel's Files page is for the server's owner or an admin, and only while
-the server is fully stopped. Each call runs a one-shot `felis files` Job in the
-`minecraft` namespace, labelled `app.kubernetes.io/managed-by=felis-files` and
+the server is fully stopped. Reads reuse a read-only `felis files` Job for the
+same world, avoiding Pod startup for every folder and file. The worker pulls
+commands from the existing internal API with a random, world-scoped token;
+each request still passes the owner/admin and stopped gates. It exits after
+45 idle seconds or four minutes total; at most four workers exist per API
+process, with one-shot reads used at capacity. No file contents are cached.
+The panel caches directory listings for 30 seconds; Refresh, a write, upload
+or restore invalidates them. The text editor highlights common config formats
+and preserves CRLF; binary and oversized files offer download instead.
+
+Changes still run one-shot Jobs in the `minecraft` namespace, labelled
+`app.kubernetes.io/managed-by=felis-files` and
 `felis.lolicon.best/files-mode=<list|read|write|mkdir|delete|rename|upload|unzip>`.
 A listing or a read holds nothing. Every change (a save, a new file or folder,
 a rename, a delete, an upload, an unzip) holds the world for its Job (§3b), so a wake or a