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+# Project: Obsidian Unicode Text Formatter Plugin
+
+## Goal
+Transform selected text in the Obsidian editor into Unicode Mathematical Alphanumeric
+Symbols (Sans-Serif Bold / Italic / Bold-Italic) for use in LinkedIn and Facebook posts.
+
+## Architecture
+- TypeScript, Obsidian Plugin API only, zero external dependencies
+- Four files to implement: src/unicode-maps.ts, src/formatter.ts, src/commands.ts, main.ts
+- Build tool: esbuild (already configured in the sample plugin template)
+
+## Key Unicode Blocks
+- Sans-Serif Bold uppercase: U+1D5D4–U+1D5ED
+- Sans-Serif Bold lowercase: U+1D5EE–U+1D607
+- Sans-Serif Bold digits:    U+1D7EC–U+1D7F5
+- Sans-Serif Italic uppercase: U+1D608–U+1D621
+- Sans-Serif Italic lowercase: U+1D622–U+1D63B
+- Sans-Serif Bold-Italic uppercase: U+1D63C–U+1D655
+- Sans-Serif Bold-Italic lowercase: U+1D656–U+1D66F
+
+## Obsidian API used
+- editor.getSelection() / editor.replaceSelection()
+- this.addCommand({ id, name, editorCallback })
+- this.addRibbonIcon()
+
+## Commands to register
+1. unicode-formatter:bold        "Format as Unicode Bold"
+2. unicode-formatter:italic      "Format as Unicode Italic"
+3. unicode-formatter:bold-italic "Format as Unicode Bold Italic"
+
+## Testing
+Install to: .obsidian/plugins/unicode-text-formatter/ (main.js + manifest.json)
+Enable in: Obsidian → Settings → Community Plugins