Feature request: use opencodeProvider for tag generation, or support streaming for memoryProvider

Problem

The memory tag migration endpoint (POST /api/migration/tags/run-batch) always uses the manual API configuration when generating tags:

• dist/services/api-handlers.js → handleRunTagMigrationBatch
• It calls buildMemoryProviderConfig(CONFIG, ...) and then AIProviderFactory.createProvider(CONFIG.memoryProvider, ...)
• The validation in dist/services/ai/provider-config.js requires all three of memoryModel / memoryApiUrl / memoryApiKey

So for users who only configured opencodeProvider + opencodeModel (the Recommended setup in opencode-mem.jsonc), clicking migrate fails immediately:

External API not configured for memory provider: missing memoryModel; missing memoryApiUrl; missing memoryApiKey

Auto-capture (auto-capture.js) and user profile learning (user-memory-learning.js) both fall back to opencodeProvider; tag migration is the only path that does not, so the behavior is inconsistent.

When it fails, the UI shows no error at all — the error response is only visible in the browser DevTools network panel, so users cannot tell why the migration failed.

Separately, the manual path with memoryProvider: openai-chat sends non-streaming requests. Some OpenAI-compatible endpoints (e.g. codebuddy) do not support non-streaming calls and return 400 Non-stream chat request is currently not supported, so migration cannot complete even with all three values configured.

Expected behavior

Both paths should work:

1. Reuse opencodeProvider: make tag migration consistent with auto-capture — prefer opencodeProvider/opencodeModel when configured, and fall back to the manual API configuration otherwise. This needs only one place to configure and no extra API key.
2. Support streaming: add an optional streaming mode for memoryProvider (or automatically retry with streaming when a non-streaming request fails), so OpenAI-compatible endpoints that only support streaming also work for tag migration.

Environment

• opencode-mem 2.34.0
• OpenCode V2
• Windows 11