feat(core): consolidate all state under a single env-aware home directory (#462) (#549)

Previously `core/config.py` defined `DEFAULT_CONFIG_DIR = Path.home() /
".openjarvis"` as a by-value module constant imported into ~45 modules, and 34
modules hardcoded `Path.home() / ".openjarvis"` directly. The installer honored
`OPENJARVIS_HOME` but the Python runtime ignored it, producing a split-brain
layout (some modules honored the override, the core config dir did not). Eval
dataset caches also scattered into `~/.cache/<benchmark>`.

This introduces a single env-aware resolver in `openjarvis/core/paths.py` and
routes every state/config/cache path through it. OpenJarvis now keeps ALL of
its state under ONE root, resolved in priority order:

  1. $OPENJARVIS_HOME
  2. $XDG_DATA_HOME/openjarvis   (single nested dir, when XDG_DATA_HOME is set)
  3. ~/.openjarvis               (default — unchanged, so existing installs are
                                  untouched and no data migration is required)

Implementation:
- New `core/paths.py`: get_config_dir / get_config_path / get_data_dir /
  get_cache_dir, with a source-tree rejection guard (fails loudly per
  REVIEW.md if the root resolves inside the repo).
- `core/config.py`: DEFAULT_CONFIG_DIR / DEFAULT_CONFIG_PATH are now resolved
  via the env-aware resolver at import (real attributes, so existing
  monkeypatch.setattr-based tests keep working). All dataclass field defaults
  that pointed at ~/.openjarvis converted to default_factory so they honor the
  override at instantiation.
- Routed all 34 hardcoders plus several string-literal escapees the original
  audit missed: prompt_loader / description_loader (were OPENJARVIS_HOME-only,
  no XDG), swebench_harness cache, tools/{memory,skill,user_profile}_manage
  defaults, server trace.db fallbacks, doctor_cmd hints.
- spec_search storage/paths now delegates to the unified resolver (gains XDG);
  its ConfigurationError is aliased to the core one.
- Eval dataset caches moved from ~/.cache/<name> to <root>/cache/<name>
  (~/.cache/huggingface left alone — it is HF's own cache).
- Docs + installer comment + `jarvis config path` to show resolved dirs.

Read-only macOS connectors and OS service files (LaunchAgents/systemd) are
intentionally left untouched.

Fixes #462

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

docs/getting-started/configuration.md

@@ -17,6 +17,46 @@ The configuration file lives at:
 
 OpenJarvis creates the `~/.openjarvis/` directory and populates it with a default config when you run `jarvis init`.
 
+## Relocating the OpenJarvis directory
+
+OpenJarvis keeps **all** of its state — config, databases, caches, logs,
+credentials, skills, recipes, connectors — under a **single root** so it never
+clutters your home directory beyond one folder. By default that root is
+`~/.openjarvis`, but you can move it.
+
+The root is resolved in priority order:
+
+1. **`$OPENJARVIS_HOME`** — explicit override. Honored by both the installer
+   and the Python runtime.
+2. **`$XDG_DATA_HOME/openjarvis`** — used when `$XDG_DATA_HOME` is set (a single
+   `openjarvis` directory nested under it, per the XDG Base Directory spec).
+3. **`~/.openjarvis`** — the default. With no environment variables set, the
+   resolved path is exactly this, so existing installs are untouched.
+
+```bash
+# Relocate the whole install + runtime tree at install time:
+OPENJARVIS_HOME=~/apps/openjarvis curl -fsSL https://open-jarvis.github.io/OpenJarvis/install.sh | bash
+
+# Or for a single run / your shell profile:
+export OPENJARVIS_HOME=~/apps/openjarvis
+```
+
+Confirm where your data lives with:
+
+```bash
+jarvis config path
+```
+
+!!! note "Migration"
+    Because the default is unchanged, **no data migration is required** for
+    existing installs. If you set `OPENJARVIS_HOME` (or `XDG_DATA_HOME`) on a
+    machine that already has data in `~/.openjarvis`, OpenJarvis will look in
+    the new location and not see your old data — move it yourself if you want
+    to keep it: `mv ~/.openjarvis "$OPENJARVIS_HOME"`.
+
+`$OPENJARVIS_CONFIG` still points at an explicit `config.toml` file
+independently of the root, if you need to override just the config file path.
+
 ## Generating Configuration
 
 ### First-Time Setup