Add status command, strip raw blobs from search, harden login flow

- Add `alpha status` command to check auth state
- Search results drop raw text blobs by default (opt-in via includeRaw)
- Clean and normalize search result fields
- Export parsePaperSearchResults for external consumers
- Login callback server handles EADDRINUSE, styled HTML pages
- Better browser open error handling on all platforms
- Search prints mode description before results

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

README.md

@@ -10,6 +10,7 @@ Research agents hallucinate paper details and forget what they learn in a sessio
 ```bash
 npm install -g @companion-ai/alpha-hub
 alpha login                        # sign in with alphaXiv
+alpha status                       # show whether alphaXiv auth is present
 alpha search "attention mechanism" # search papers
 alpha get 1706.03762               # fetch paper report
 ```
@@ -52,6 +53,7 @@ alpha ask 1706.03762 "What datasets were used for evaluation?"
 | `alpha annotate <id> --clear` | Remove a note |
 | `alpha annotate --list` | List all notes |
 | `alpha login` | Sign in with alphaXiv |
+| `alpha status` | Show alphaXiv authentication status |
 | `alpha logout` | Sign out |
 
 All commands accept `--json` for machine-readable output.