fix(admin): implement ApplyPluginConfigFromToml to propagate settings (#10388)

* fix(admin): implement ApplyPluginConfigFromToml to propagate settings to plugin config store

* Update weed/admin/dash/config_toml.go

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

* admin: overlay admin.toml onto plugin configs through bootstrap defaults

Creating a config from scratch at startup skipped the descriptor-defaults
bootstrap, so a job type with only worker keys in admin.toml persisted
Enabled=false and RetryLimit=0 and silently stopped running. Overlay
existing configs at startup, and apply the same overlay in
enrichConfigDefaults when the plugin bootstraps a fresh config from
descriptor defaults.

Also place collection_filter in the admin values where workers read it,
map preferred_tags as a string list, and stamp UpdatedAt.

* admin: trim the admin.toml help text and call-site comment

* admin: clamp toml retry values to the int32 range

* admin: fail startup when admin.toml cannot reach the plugin config

The legacy overlay already aborts startup when declared settings cannot
persist; continuing here would let workers bootstrap with stale values.

* admin: fix the retry clamp test on 32-bit

A 32-bit int cannot hold the oversized toml value, so viper returns 0
before the clamp runs.

---------

Co-authored-by: baracudaz <baracudaz@users.noreply.github.com>
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>
Co-authored-by: Chris Lu <chris.lu@gmail.com>

weed/command/admin.go

@@ -181,6 +181,8 @@ var cmdAdmin = &Command{
       saved from the admin UI, so they can be managed declaratively
     - Requires -dataDir; values can also be set via WEED_* environment
       variables, e.g. WEED_MAINTENANCE_VACUUM_GARBAGE_THRESHOLD=0.3
+    - Settings are applied to both the legacy task policy and the plugin
+      config store, so they take effect for the admin UI and plugin workers
     - Generate example admin.toml: weed scaffold -config=admin
 
   Configuration File:
@@ -388,6 +390,10 @@ func startAdminServer(ctx context.Context, options AdminOptions, enableUI bool,
 	// Create admin server (plugin is always enabled)
 	adminServer := dash.NewAdminServer(*options.master, *options.filerGroup, nil, dataDir, icebergPort)
 
+	if err := adminServer.ApplyPluginConfigFromToml(util.GetViper()); err != nil {
+		return fmt.Errorf("apply admin.toml to plugin config: %w", err)
+	}
+
 	// Show discovered filers
 	filers := adminServer.GetAllFilers()
 	if len(filers) > 0 {