fix(proxy): resolve merge conflict in claude adapter — combine smart URL path detection with beta=true

Merge both features from feat/smart-url-path-detection and main:
- Smart URL path detection: skip appending endpoint when base_url already ends with API path
- URL suffix preservation: preserve query/fragment from base_url via split_url_suffix
- v1 dedup: boundary-safe deduplication of /v1/v1
- ?beta=true: auto-append for /v1/messages endpoints (DuckCoding compatibility)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

src/lib/api/skills.ts

@@ -45,6 +45,7 @@ export interface UnmanagedSkill {
   name: string;
   description?: string;
   foundIn: string[];
+  path: string;
 }
 
 /** 技能对象（兼容旧 API） */

src/lib/schemas/settings.ts

@@ -33,6 +33,7 @@ export const settingsSchema = z.object({
   webdavSync: z
     .object({
       enabled: z.boolean().optional(),
+      autoSync: z.boolean().optional(),
       baseUrl: z.string().trim().optional().or(z.literal("")),
       username: z.string().trim().optional().or(z.literal("")),
       password: z.string().optional(),
@@ -42,6 +43,7 @@ export const settingsSchema = z.object({
         .object({
           lastSyncAt: z.number().nullable().optional(),
           lastError: z.string().nullable().optional(),
+          lastErrorSource: z.string().nullable().optional(),
           lastRemoteEtag: z.string().nullable().optional(),
           lastLocalManifestHash: z.string().nullable().optional(),
           lastRemoteManifestHash: z.string().nullable().optional(),