fix(config): accept legacy dream/distill config keys with warning

[rekty]

Users setting `enabled`/`intervalDays` (camelCase) in dream/distill config sections get silently ignored because the schema only accepts `auto`/`interval_days`. Add pre-validation normalization that maps legacy keys to canonical names and logs a deprecation warning.

Fixes #2135

Issue / context (if applicable)

Type of change

Bug fix / New feature / Refactor / Documentation — keep the ones that apply and delete the rest.

What does this PR do?

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Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[rekty]

Hey! This PR fixes #2135 by adding normalization for legacy / config keys. Users setting or will now see a deprecation warning and the values get mapped to the canonical / keys. Ready for review!

[rekty]

Hi! CI workflows (lint, test, typecheck) havent started yet — this is likely because GitHub requires first-time contributor approval for workflow runs. Could you please approve the CI runs on the Actions tab? Thanks!

[rekty]

cc @MiMoHardFather @wqymi @yanyihan-xiaomi — could one of you approve the CI workflow runs for this fork PR? The lint/test/typecheck checks are waiting on approval. Thanks!

[rekty]

Hi @MiMoHardFather @yanyihan-xiaomi @wqymi 👋

I've submitted 8 PRs fixing various issues on Windows and cross-platform compatibility. All PRs are ready for review but CI workflows haven't been triggered yet because they're from a fork.

Could you please approve the workflow runs for these PRs? Here's a summary:

PR	Fix	Impact
#2229	Legacy dream/distill config keys	Backward compatibility
#2230	FFmpeg fallback for Windows audio	Windows voice support
#2242	Enter key swallowed by empty autocomplete	Core UX bug
#2244	Missing finish_reason treated as error	Crash fix
#2245	Cron fires routed to wrong session	Cron reliability
#2247	Long lines in Windows esbuild	Desktop build fix
#2248	Bare permission words in env var	Config flexibility
#2249	Light mode text too bright	Windows theme fix

To approve workflow runs: go to any PR → Files changed tab → click Awaiting approval → Approve workflows to run.

Happy to address any feedback! 🙏