fix(tiktok): default content_posting_method to DIRECT_POST

[giladresisi]

Problem

Scheduled TikTok posts were being marked successful in Postiz and Temporal but never published. The postSocial activity returned postId: "missing" with a tiktok.com/messages release URL.

Root cause: the post had content_posting_method: "UPLOAD" instead of DIRECT_POST. UPLOAD does not publish — TikTok's API delivers the video to the account's app inbox, where the user must manually complete it within ~24h or it's discarded. This is TikTok's SEND_TO_USER_INBOX terminal status, which we (correctly) treat as a successful upload.

Why the agent chose UPLOAD: the chat/MCP agent had to supply content_posting_method with no guidance — it's a bare required enum ('DIRECT_POST' | 'UPLOAD') with no description or default, and TikTok's agent @Rules said nothing about it. For a video post, "UPLOAD" reads like the obvious choice. The user never asked for it; the model guessed.

Fix (two layers)

• @Rules guidance (tiktok.provider.ts): the agent is now told to use DIRECT_POST unless the user explicitly asks to review/edit inside the TikTok app first, and that UPLOAD does not publish.
• Hard default (integration.schedule.post.ts): a PROVIDER_SETTINGS_DEFAULTS map + buildSettings() helper fills content_posting_method with DIRECT_POST when the key is omitted — applied in both the validation and creation paths — so an omitted value can never land on UPLOAD by accident. The default map is TikTok-only; all other providers reduce to the exact prior behavior.

Testing

• Validated live over MCP: scheduling a TikTok draft omitting content_posting_method now yields DIRECT_POST.
• Behavior-preserving for non-TikTok providers (defaults map has only a tiktok entry).
• Typechecks (backend).

Notes

First of two related changes. A follow-up feature branch (agent list/update of scheduled posts) stacks on this one and will be opened as a separate PR.

🤖 Generated with Claude Code

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