feat(plugins): add JSONForms-based plugin configuration UI (#4911)

* feat(plugins): add JSONForms schema for plugin configuration

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: enhance error handling by formatting validation errors with field names

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: enforce required fields in config validation and improve error handling

Signed-off-by: Deluan <deluan@navidrome.org>

* format JS code

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: add config schema validation and enhance manifest structure

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: refactor plugin config parsing and add unit tests

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: add config validation error message in Portuguese

* feat: enhance AlwaysExpandedArrayLayout with description support and improve array control testing

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: update Discord Rust plugin configuration to use JSONForm for user tokens and enhance schema validation

Signed-off-by: Deluan <deluan@navidrome.org>

* fix: resolve React Hooks linting issues in plugin UI components

* Apply suggestions from code review

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

* format code

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: migrate schema validation to use santhosh-tekuri/jsonschema and improve error formatting

Signed-off-by: Deluan <deluan@navidrome.org>

* address PR comments

Signed-off-by: Deluan <deluan@navidrome.org>

* fix flaky test

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: enhance array layout and configuration handling with AJV defaults

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: implement custom tester to exclude enum arrays from AlwaysExpandedArrayLayout

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: add error boundary for schema rendering and improve error messages

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: refine non-enum array control logic by utilizing JSONForms schema resolution

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: add error styling to ToggleEnabledSwitch for disabled state

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: adjust label positioning and styling in SchemaConfigEditor for improved layout

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: implement outlined input controls renderers to replace custom fragile CSS

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: remove margin from last form control inside array items for better spacing

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: enhance AJV error handling to transform required errors for field-level validation

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: set default value for User Tokens in manifest.json to improve user experience

Signed-off-by: Deluan <deluan@navidrome.org>

* format

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: add margin to outlined input controls for improved spacing

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: remove redundant margin rule for last form control in array items

Signed-off-by: Deluan <deluan@navidrome.org>

* feat: adjust font size of label elements in SchemaConfigEditor for improved readability

Signed-off-by: Deluan <deluan@navidrome.org>

---------

Signed-off-by: Deluan <deluan@navidrome.org>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

plugins/testdata/test-config/manifest.json

@@ -2,5 +2,60 @@
   "name": "Test Config Plugin",
   "author": "Navidrome Test",
   "version": "1.0.0",
-  "description": "A test plugin for config service integration testing"
+  "description": "A test plugin for config service integration testing",
+  "config": {
+    "schema": {
+      "type": "object",
+      "properties": {
+        "api_key": {
+          "type": "string",
+          "title": "API Key",
+          "minLength": 1
+        },
+        "max_retries": {
+          "type": "string",
+          "title": "Max Retries"
+        },
+        "timeout": {
+          "type": "string",
+          "title": "Timeout"
+        },
+        "users": {
+          "type": "array",
+          "title": "Users",
+          "items": {
+            "type": "object",
+            "properties": {
+              "username": {
+                "type": "string",
+                "title": "Username",
+                "minLength": 1
+              },
+              "token": {
+                "type": "string",
+                "title": "Token",
+                "minLength": 1
+              }
+            },
+            "required": ["username", "token"]
+          }
+        },
+        "settings": {
+          "type": "object",
+          "title": "Settings",
+          "properties": {
+            "enabled": {
+              "type": "boolean",
+              "title": "Enabled"
+            },
+            "count": {
+              "type": "integer",
+              "title": "Count"
+            }
+          }
+        }
+      },
+      "required": ["api_key"]
+    }
+  }
 }