docs: update garden.md with documentation overview and future plans

garden.md

@@ -27,6 +27,19 @@ Hosts in this repo are named after plants and flowers.
 - `home/default.nix` — shared home-manager config for user `michaotic` (plan to migrate to `mikl` later)
 - `secrets/` — sops-encrypted secrets per host
 
+## documentation
+
+notes are split by topic under `docs/`:
+
+- `docs/structure.md` — high-level overview, where things go
+- `docs/poppy.md` — MacBook specific (homebrew, system defaults)
+- `docs/muscari.md` — server + k3s specifics
+- `docs/shell.md` — zsh, pure prompt, plugins
+- `docs/terminal.md` — kitty + catppuccin theme
+- `docs/cheatsheet.md` — quick commands reference
+
+when adding a new host: copy `docs/structure.md` template, document hostname, role, packages unique to it.
+
 ## migrations
 
 - `nix-config-legacy/` — previous muscari-only config (preserved for reference)
@@ -42,3 +55,21 @@ currently using `michaotic` as username (historical). plan to migrate to `mikl`
 - linux: easier, but better to do in one coordinated change
 
 **when:** after setting up proper backups and testing migration procedure
+
+### rosemary setup
+
+currently `flake.nix` has `rosemary` commented out. need to:
+- add disk config (likely similar to muscari)
+- add users.users.michaotic.openssh.authorizedKeys
+- test `nix flake check`
+
+### documentation improvements
+
+- [ ] create `docs/bootstrap.md` — manual setup guide for fresh device without nix (emergency fallback)
+  - list all CLI tools and how to install via brew/pnpm
+  - list all system defaults that need manual configuration
+  - explain which tools are nix-managed vs brew-managed
+- [ ] create `docs/adding-host.md` — checklist for adding a new host
+- [ ] create `docs/secrets.md` — sops-nix setup when we get there
+- [ ] add migration notes to `docs/structure.md` as we learn patterns
+- [ ] screenshots/notes for things that aren't obvious (e.g. dock layout)