apps: add second-brain — self-improving Second Brain on Oracle AI Database 26ai

[LindaHaviv]

What this adds

apps/second-brain — the companion code for the 1P article "Build a self-improving Second Brain on Oracle AI Database 26ai" (in review with the Oracle DevRel team via Freeman & Forrest).

A personal second brain: your posts, videos, notes, and AI chats unified in one Oracle AI Database 26ai —

• Semantic search over in-database ONNX embeddings (no external vector store)
• Self-compiling wiki: topic pages synthesized from your own content
• Agent memory via OAMP, with privacy-scoped retrieval (a visibility column filters every read path, including memory recall)
• MCP server so Claude, ChatGPT, or any MCP client can research your brain
• Runs fully local and headless (container image + Python), with optional lift to Oracle Autonomous Database
• Ships with a hands-on workshop (docs/TUTORIAL.md), eval suites for retrieval/grounding/privacy, and three prompts that let readers build their version with their AI coding agent

Also adds the row to the apps/ index table (formatted with the repo's Prettier config).

Notes for reviewers

• The living, continuously evolving version is maintained at LindaHaviv/second-brain; this folder is a snapshot pinned to what the article describes, and its README says so.
• docs/BLOG.md is the article draft itself — happy to remove it from this folder if you prefer to avoid duplication once the article is hosted.
• The folder currently carries the author's MIT LICENSE — happy to swap to UPL 1.0 to match the other apps if that's your convention for contributions.
• The only third-party materials in the folder are four OFL 1.1 web fonts (Fraunces, Orbitron, Virgil), now disclosed with the full license text in THIRD_PARTY_LICENSES.md; everything else is the author's original work.
• OCA: signature in progress for linda.haviv@gmail.com (the commit author email).

🤖 Generated with Claude Code

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