Stop tracking fiction, and stop carrying 80 MiB of wallpaper per clone

Three things were in history that should not have been, all invisible to the
tool that deploys them:

- `home/dank/.omp/dotfiles/**` — 3 files re-hosting `niri/cfg/autostart.kdl`,
  `niri/cfg/keybinds.kdl` and `systemd-user/…/swayidle-lock.service` under a
  prefix `scripts/deploy.sh` never reads (it walks `dotfiles/<pkg>/`). The live
  package is deployed and symlinked, so the copy asserted nothing; it only
  misled. Moved to `.AGENTTRASH/20261020-tracked-debt/`.
- `.pre-pull-backup/**` — 2 managed-skill files, a local backup in history,
  which `.gitignore` itself declares must stay on disk only. Same destination.
- `dotfiles/noctalia/.local/share/noctalia/wallpapers/` — 23 images, 80.4 MiB.
  Untracked, files left in place: `~/.local/share/noctalia/wallpapers` symlinks
  into this directory and the theme reads it, so deleting them would have gone
  black. Every filename carries its wallhaven ID, so a fresh box restores the
  set with one `curl` per file plus `deploy.sh`; losing the set is an acceptable
  outcome, 80 MiB per clone forever is not.

New page `omp-docs/tools/dotfiles-deploy.md` owns the deploy contract (the
`--check`/sync/`--adopt` modes, `zz-$(hostname)` override semantics, the dconf
and systemd-user special cases) because nothing documented it, plus two laws:
media the pipeline consumes is content not config, and `systemctl --user
enable` snapshots an absolute path — so enabling from a worktree means the
seven-day reap silently kills the unit while `is-enabled` keeps answering
`enabled`. That second law is not theoretical:
`default.target.wants/blankpad-desk-autoswitch.service` pointed into the reaped
`wt/de-redesign-20261009` and desk auto-switching had been off since. It is
relinked to `dotfiles/zz-blankpad/` and left inactive rather than started mid-
session; starting it applies a desk profile.

Refs #40

.pre-pull-backup/agent/managed-skills/stash-supersession-audit-before-drop/SKILL.md

@@ -1,33 +0,0 @@
----
-name: stash-supersession-audit-before-drop
-description: "Before dropping a stale git stash, prove it's superseded by HEAD via per-file line-set diff of git show stash@{0}:file vs HEAD; archive as an annotated tag and drop only after auditing unique facts — zero-loss alternative to blind drop."
----
-
-# Stash Supersession Audit Before Drop
-
-Use when a repo (especially a live-deployment checkout where the working tree IS the deployment, e.g. `~/.omp` command-center) has an old stash whose content may have been superseded by later commits, and dropping blindly risks losing unique facts.
-
-## Procedure
-
-1. **Inventory the stash** — see which files it touches:
-   ```bash
-   git stash show --stat stash@{0}
-   ```
-2. **Probe for unique content per file.** For each touched file, diff stash version against HEAD and count lines that exist only in the stash version:
-   ```bash
-   git show "stash@{0}:<path>" > /tmp/stash_copy
-   # compare normalized line sets; report lines present in stash but absent from HEAD
-   ```
-   A file with `unique-vs-HEAD = 0` is fully superseded — safe to drop for that file.
-3. **Classify each unique-content hit**:
-   - *Stale fact* (superseded by a later refactor, e.g. old model/provider naming) → drop is correct.
-   - *Live durable fact* (e.g. an operational invariant never re-recorded) → extract it into the live memory/docs file or flag to the user before dropping.
-4. **Archive before dropping** — zero-loss: tag the stash commit, then drop from the stash list:
-   ```bash
-   git tag archive/stash-<YYYY-MM-DD>-<base-branch>-wip "stash@{0}"
-   git stash drop "stash@{0}"
-   ```
-   The tag pins the full stash object (including its index parent); recoverable later via `git show archive/stash-...` or `git checkout archive/stash-...^3 -- <path>` for the untracked-files third parent if present.
-
-## Why
-Stashes are invisible in normal history and expire from reflogs (~90 days). A stash that *looks* superseded can still hold the only copy of a durable fact; tagging converts "drop" into a reversible archive with zero workflow cost.