fix(discord): harden voice DAVE receive reliability (#25861)

Reimplements and consolidates related work:
- #24339 stale disconnect/destroyed session guards
- #25312 voice listener cleanup on stop
- #23036 restore @snazzah/davey runtime dependency

Adds Discord voice DAVE config passthrough, repeated decrypt failure
rejoin recovery, regression tests, docs, and changelog updates.

Co-authored-by: Frank Yang <frank.ekn@gmail.com>
Co-authored-by: Do Cao Hieu <admin@docaohieu.com>

src/config/zod-schema.providers-core.ts

@@ -315,6 +315,8 @@ const DiscordVoiceSchema = z
   .object({
     enabled: z.boolean().optional(),
     autoJoin: z.array(DiscordVoiceAutoJoinSchema).optional(),
+    daveEncryption: z.boolean().optional(),
+    decryptionFailureTolerance: z.number().int().min(0).optional(),
     tts: TtsConfigSchema.optional(),
   })
   .strict()