refactor(pi-devin): switch from npm+patch to vendored local fork

- Vendor the patched pi-devin@0.1.2 tree at apps/pi-devin/upstream/
  (third-party archive -> upstream_fork); git history replaces the patch
  layer as the change archive. Includes the devin-desktop identity fix
  and normalized catalog variant mapping from the previous patch.
- build-pi-package.sh now verifies source.sha256 against
  host-local-packages.json and npm-packs the vendored tree; drop the
  npm fetch + patch stage.
- install-pi-package.sh strips the npm-pack package/ prefix to match
  the playbook's unarchive behavior.
- Deployed to a100 via deploy_pi_devin_package (--limit a100, R2 then
  R3); remote verified to carry the fork source.

README.md

@@ -16,9 +16,9 @@ Those models are available through the local Devin CLI. This package uses that C
 
 ## Requirements
 
-- Pi Coding Agent 0.86+
+- Pi Coding Agent 0.80+
 - A signed-in [Devin CLI](https://docs.devin.ai/cli) (`devin auth status`)
-- Node 22.19+ (required by Pi 0.86)
+- Node 18+
 
 The CLI binary is resolved in this order:
 
@@ -27,8 +27,6 @@ The CLI binary is resolved in this order:
 3. Devin.app's bundled `devin` binary
 4. `which devin`
 
-On Windows, discovery checks the CLI installer and Devin Desktop locations, then uses `where.exe` to search PATH. Native executables and `.cmd`/`.bat` wrappers are supported, including paths with spaces. `DEVIN_CLI` takes precedence on every platform.
-
 ## Install
 
 From git:
@@ -37,16 +35,12 @@ From git:
 pi install git:github.com/kashyab12/pi-devin
 ```
 
-From npm:
+After npm publish:
 
 ```bash
 pi install npm:pi-devin
 ```
 
-Version 0.2.0 requires Pi 0.86+ and Node 22.19+. It restores system instructions and tools on the current Pi transcript format and sends system instructions through Devin's dedicated prompt field. Version 0.1.2 predates Pi 0.86 support.
-
-`pi-devin-local` is a separate npm package maintained in the [mizorewww/pi-devin fork](https://github.com/mizorewww/pi-devin). Changes merged here do not update that package. Install only one: both packages register the `devin` provider, so their registrations can overwrite each other.
-
 Local checkout:
 
 ```bash
@@ -71,8 +65,6 @@ Commands:
 - `/devin-status` — CLI path, version, auth
 - `/devin-refresh` — reload `devin models list --format json`
 
-The model catalog is cached for six hours in `$XDG_CACHE_HOME/pi-devin/models.json` (or `~/.cache/pi-devin/models.json`). A fresh cache avoids the CLI call at startup; an older cache remains available while it refreshes in the background. Set `PI_OFFLINE=1` to skip automatic catalog refreshes. `/devin-refresh` still requests a refresh explicitly.
-
 ## What this is / is not
 
 | This package | Not this package |