feat: donation banner, About tab, settings UI improvements

- Dismissible donation/open-source banner after 3+ sessions (30-day snooze)
- New About tab in Settings: version, repo link, license info
- Centralize project URLs (REPO_URL, DONATE_URL) in __init__.py, served via /health
- Center settings tab bar, reduce tab padding for 6-tab fit
- External URL save button: icon button instead of full-width text button
- Remove redundant settings footer close button
- Footer "Source Code" link replaced with "About" opening settings
- i18n keys for en/ru/zh

server/src/wled_controller/api/routes/system.py

@@ -13,7 +13,7 @@ from typing import Optional
 import psutil
 from fastapi import APIRouter, Depends, HTTPException, Query
 
-from wled_controller import __version__
+from wled_controller import __version__, REPO_URL, DONATE_URL
 from wled_controller.api.auth import AuthRequired, is_auth_enabled
 from wled_controller.api.dependencies import (
     get_audio_source_store,
@@ -54,7 +54,11 @@ logger = get_logger(__name__)
 psutil.cpu_percent(interval=None)
 
 # GPU monitoring (initialized once in utils.gpu, shared with metrics_history)
-from wled_controller.utils.gpu import nvml_available as _nvml_available, nvml as _nvml, nvml_handle as _nvml_handle  # noqa: E402
+from wled_controller.utils.gpu import (  # noqa: E402
+    nvml_available as _nvml_available,
+    nvml as _nvml,
+    nvml_handle as _nvml_handle,
+)
 
 
 def _get_cpu_name() -> str | None:
@@ -77,9 +81,7 @@ def _get_cpu_name() -> str | None:
                         return line.split(":")[1].strip()
         elif platform.system() == "Darwin":
             return (
-                subprocess.check_output(
-                    ["sysctl", "-n", "machdep.cpu.brand_string"]
-                )
+                subprocess.check_output(["sysctl", "-n", "machdep.cpu.brand_string"])
                 .decode()
                 .strip()
             )
@@ -107,6 +109,8 @@ async def health_check():
         version=__version__,
         demo_mode=get_config().demo,
         auth_required=is_auth_enabled(),
+        repo_url=REPO_URL,
+        donate_url=DONATE_URL,
     )
 
 
@@ -131,12 +135,22 @@ async def list_all_tags(_: AuthRequired):
     """Get all tags used across all entities."""
     all_tags: set[str] = set()
     from wled_controller.api.dependencies import get_asset_store
+
     store_getters = [
-        get_device_store, get_output_target_store, get_color_strip_store,
-        get_picture_source_store, get_audio_source_store, get_value_source_store,
-        get_sync_clock_store, get_automation_store, get_scene_preset_store,
-        get_template_store, get_audio_template_store, get_pp_template_store,
-        get_pattern_template_store, get_asset_store,
+        get_device_store,
+        get_output_target_store,
+        get_color_strip_store,
+        get_picture_source_store,
+        get_audio_source_store,
+        get_value_source_store,
+        get_sync_clock_store,
+        get_automation_store,
+        get_scene_preset_store,
+        get_template_store,
+        get_audio_template_store,
+        get_pp_template_store,
+        get_pattern_template_store,
+        get_asset_store,
     ]
     for getter in store_getters:
         try:
@@ -209,15 +223,11 @@ async def get_displays(
     except EntityNotFoundError as e:
         raise HTTPException(status_code=404, detail=str(e))
 
-
     except ValueError as e:
         raise HTTPException(status_code=400, detail=str(e))
     except Exception as e:
         logger.error("Failed to get displays: %s", e, exc_info=True)
-        raise HTTPException(
-            status_code=500,
-            detail="Internal server error"
-        )
+        raise HTTPException(status_code=500, detail="Internal server error")
 
 
 @router.get("/api/v1/system/processes", response_model=ProcessListResponse, tags=["Config"])
@@ -235,10 +245,7 @@ async def get_running_processes(_: AuthRequired):
         return ProcessListResponse(processes=sorted_procs, count=len(sorted_procs))
     except Exception as e:
         logger.error("Failed to get processes: %s", e, exc_info=True)
-        raise HTTPException(
-            status_code=500,
-            detail="Internal server error"
-        )
+        raise HTTPException(status_code=500, detail="Internal server error")
 
 
 @router.get(
@@ -260,9 +267,7 @@ def get_system_performance(_: AuthRequired):
         try:
             util = _nvml.nvmlDeviceGetUtilizationRates(_nvml_handle)
             mem_info = _nvml.nvmlDeviceGetMemoryInfo(_nvml_handle)
-            temp = _nvml.nvmlDeviceGetTemperature(
-                _nvml_handle, _nvml.NVML_TEMPERATURE_GPU
-            )
+            temp = _nvml.nvmlDeviceGetTemperature(_nvml_handle, _nvml.NVML_TEMPERATURE_GPU)
             gpu = GpuInfo(
                 name=_nvml.nvmlDeviceGetName(_nvml_handle),
                 utilization=float(util.gpu),

server/src/wled_controller/api/schemas/system.py

@@ -13,7 +13,11 @@ class HealthResponse(BaseModel):
     timestamp: datetime = Field(description="Current server time")
     version: str = Field(description="Application version")
     demo_mode: bool = Field(default=False, description="Whether demo mode is active")
-    auth_required: bool = Field(default=True, description="Whether API key authentication is required")
+    auth_required: bool = Field(
+        default=True, description="Whether API key authentication is required"
+    )
+    repo_url: str = Field(default="", description="Source code repository URL")
+    donate_url: str = Field(default="", description="Donation page URL")
 
 
 class VersionResponse(BaseModel):
@@ -84,6 +88,7 @@ class RestoreResponse(BaseModel):
 
 # ─── Auto-backup schemas ──────────────────────────────────────
 
+
 class AutoBackupSettings(BaseModel):
     """Settings for automatic backup."""
 
@@ -119,6 +124,7 @@ class BackupListResponse(BaseModel):
 
 # ─── MQTT schemas ──────────────────────────────────────────────
 
+
 class MQTTSettingsResponse(BaseModel):
     """MQTT broker settings response (password is masked)."""
 
@@ -138,17 +144,22 @@ class MQTTSettingsRequest(BaseModel):
     broker_host: str = Field(description="MQTT broker hostname or IP")
     broker_port: int = Field(ge=1, le=65535, description="MQTT broker port")
     username: str = Field(default="", description="MQTT username (empty = anonymous)")
-    password: str = Field(default="", description="MQTT password (empty = keep existing if omitted)")
+    password: str = Field(
+        default="", description="MQTT password (empty = keep existing if omitted)"
+    )
     client_id: str = Field(default="ledgrab", description="MQTT client ID")
     base_topic: str = Field(default="ledgrab", description="Base topic prefix")
 
 
 # ─── External URL schema ───────────────────────────────────────
 
+
 class ExternalUrlResponse(BaseModel):
     """External URL setting response."""
 
-    external_url: str = Field(description="External base URL (e.g. https://myserver.example.com:8080). Empty = use auto-detected URL.")
+    external_url: str = Field(
+        description="External base URL (e.g. https://myserver.example.com:8080). Empty = use auto-detected URL."
+    )
 
 
 class ExternalUrlRequest(BaseModel):
@@ -159,10 +170,13 @@ class ExternalUrlRequest(BaseModel):
 
 # ─── Log level schemas ─────────────────────────────────────────
 
+
 class LogLevelResponse(BaseModel):
     """Current log level response."""
 
-    level: str = Field(description="Current effective log level name (e.g. DEBUG, INFO, WARNING, ERROR, CRITICAL)")
+    level: str = Field(
+        description="Current effective log level name (e.g. DEBUG, INFO, WARNING, ERROR, CRITICAL)"
+    )
 
 
 class LogLevelRequest(BaseModel):