[Misc] Follow platform conventions for the default work directory

[ClementEXWiki]

Jira URL

N/A

Changes

Description

• Default work-directory root is now $XDG_STATE_HOME/xwiki-llm (falling back to ~/.local/state/xwiki-llm) on Linux/macOS, and %LOCALAPPDATA%\xwiki-llm on Windows, instead of the unconditional ~/.xwiki-llm/work used on every OS. XWIKI_LLM_WORK still overrides it.
• Update README.md, xwiki-org.md and the two skill docs that restated the old default.
• Bump the plugin version to 1.4.2.

Clarifications

• Data directory conventions should be followed on all platforms
• Follows discussion in https://forum.xwiki.org/t/change-the-default-fallback-for-xwiki-llm-work-in-the-xwiki-llm-plugin/18804

Screenshots & Video

N/A

Executed Tests

N/A

Expected merging strategy

• Prefers squash: Yes
• Backport on branches:
  *

[vmassol]

I've pushed a merge of master onto this branch (7b59f33) that resolves the conflicts and follows up on two points. Summary of what changed and why:

Conflicts. They were version-only: master had moved to 1.5.0 while this branch carried 1.4.2. Resolved on 1.5.0 and bumped to 1.5.1 for this change, in all four manifests.

The rule was incomplete. defaultWorkRoot() did handle the unset case, but every doc restated only the env-var half ($XDG_STATE_HOME/xwiki-llm), which is not what a reader gets on a stock macOS or Windows box — neither variable is set by default there, so the fallback is the common path, not the edge case. The full resolution is now written out once, in the XWIKI_LLM_WORK row of README.md's environment-variable table:

platform	variable set	variable unset
Linux/macOS	$XDG_STATE_HOME/xwiki-llm/work	~/.local/state/xwiki-llm/work
Windows	%LOCALAPPDATA%\xwiki-llm\work	%USERPROFILE%\AppData\Local\xwiki-llm\work

All four branches are verified by running the hook, simulating win32 for the two Windows ones.

Duplication. Two kinds, both removed:

• In code — master meanwhile added xwiki-it-slot.mjs, which computes its own ~/.xwiki-llm/it-slots. Left as it was, the plugin would own two unrelated roots on a developer's machine and follow the platform convention in only one of them. There is now a single xwiki/scripts/state-dir.mjs (stateRoot(), workRoot(), itSlotDir()), imported by both the SessionStart hook and the slot script, so the platform rules exist in exactly one place and everything lives under one root: <state>/xwiki-llm/{work,it-slots}.
• In prose — the platform formula was restated in five places (README twice, xwiki-org.md, conversion-plan.md, the xwiki-doc-writing tools README). The hook already appends the resolved absolute path to the injected conventions, so those files no longer need the formula at all and now just say "the work directory". That also buys back bytes in xwiki-org.md, which is injected into every session and is budget-checked.

Two judgment calls worth calling out, happy to revert either:

• The default root gained a /work segment (<state>/xwiki-llm/work, not <state>/xwiki-llm) so that it-slots can sit beside it under the one root — the exact analogue of the old ~/.xwiki-llm/work layout.
• instructions/xwiki-org.md is read verbatim by opencode, which has no SessionStart hook to append the resolved path. Pointing it only at "the end of this file" would therefore have left opencode users with no definition at all, so state-dir.mjs is also runnable — node "$XWIKI_LLM_HOME/xwiki/scripts/state-dir.mjs" prints the work root — and the instruction names that as the fallback.

Migration. Since the default moves, the hook now checks ~/.xwiki-llm/work and, for as long as anything is still in it, appends a notice asking the developer to move its contents (or to point XWIKI_LLM_WORK at the old path), explicitly telling the agent not to move or delete anything itself. It disappears once the directory is empty or gone. Confirmed firing on a machine that still has files there.

node scripts/validate.mjs and claude plugin validate ./xwiki both pass, and CI is green.