* fix: harden local data boundaries
Bind the capabilities dashboard exclusively to loopback and reject untrusted Host and Origin values. Constrain project-configured agent data paths to the Cursor data root, and harden lifecycle repair/uninstall operations against state-file traversal, symlink swaps, unsafe sources, and forged install-state destinations.\n\nCloses #2506
* fix: eliminate repair source read race
Read source bytes and mode from one no-follow file descriptor so a path replacement cannot mix metadata from one inode with content from another. Add a regression that rejects separate path-based source metadata lookup.
* fix: close dashboard hardening review gaps
