Migrate the Courses Semiotics & Semantics batches (22 files) #28

• Series: Courses
• Files: 22
• Estimated time: ~45 minutes
• Labels: good-first-issue, i16-translations

Two single-part course items from Lorena Sganzerla's 2023 "Active Inference for the Social Sciences" series still hold full 11-language sets: the Discussion item (stem "Semiotics and Semantics Discussion ~ Lorena Sganzerla ~ Active Inference for Social Sciences 9 12" → sole part MrAiB9X7Ock) and the Lecture item (stem "CCL2023.06 Semiotics and Semantics Lecture ~ Lorena Sganzerla, 2023-08-30" → sole part 4ijYLWm4P2I). The stems differ from the part titles only by date/course-code tokens.

Scope (from the triage doc, Part A):

• Item Courses/ActiveInferenceForTheSocialSciences/SemioticsSemantics_Discussion
  • 11 files, stem Semiotics and Semantics Discussion ~ Lorena Sganzerla ~ Active Inference for Social Sciences 9 12 → target translations/MrAiB9X7Ock.<bcp47>.srt
• Item Courses/ActiveInferenceForTheSocialSciences/SemioticsSemantics_Lecture
  • 11 files, stem CCL2023.06 Semiotics and Semantics Lecture ~ Lorena Sganzerla, 2023-08-30 → target translations/4ijYLWm4P2I.<bcp47>.srt

Read first: docs/volunteer-transcript-tasks.md —
sections "The 30-minute task (per file)" and "Exact command pattern".

Steps, per file:

1. Verify the guessed video_id in the item's metadata.json + a YouTube spot-check of the part.
2. Confirm the language by opening the .srt (normalize legacy codes per the migration map).
3. Move with the two-step git mv into translations/<video_id>.<bcp47>.srt.
4. Append the original repo-relative path to the destination item's metadata.json previous_paths.
5. One path-scoped commit per item: translations(<series>): migrate <N> legacy files (I16 triage).

Acceptance criteria:

• every listed file moved (or deleted, if byte-identical to an already-migrated target) with previous_paths recorded
• no listed file remains in the item's Translations/ folder; empty Translations/ and translations_tmp/ removed
• spot-checked target files open as valid subtitles and match the verified part/language