chore(xtask): rename strand branch prefix beads/ -> braid/

bd-yjh1y117. Add a shared strand_branch() helper emitting braid/<leaf>, used by
create-worktree and switch-task; update the worktree conventions and skill docs.
The beads/ prefix was a historical git namespace from before the braid migration;
remote work-type prefixes (bugfix/, feature/) are unchanged.

Author: shikokuchuo

.claude/rules/worktrees.md

@@ -36,7 +36,7 @@ the *shape* of the work, not on the strand boundary.
 
   That switches the current worktree to `feature/q2-preview-command`,
   fast-forward-pulls (so any sibling sub-tasks that merged in the
-  meantime show up), creates a fresh `beads/bd-yxqt-<slug>` topic
+  meantime show up), creates a fresh `braid/bd-yxqt-<slug>` topic
   branch off the new tip, marks the braid strand `in_progress` (via
   `braid update`), and rewrites the `CLAUDE.local.md` context block.
   Omit `--from` to branch off the current HEAD.
@@ -53,7 +53,7 @@ Each sub-task lives on its own topic branch. When a sub-task closes:
 
 ```bash
 git switch feature/q2-preview-command
-git merge --no-ff beads/<id>-<slug>
+git merge --no-ff braid/<id>-<slug>
 git push origin feature/q2-preview-command
 ```
 
@@ -70,17 +70,18 @@ All worktrees live in `.worktrees/` at the project root. This directory is git-i
 ## Branch naming
 
 - **GH issue triage worktree** → branch `issue-<N>` at `.worktrees/issue-<N>/`. Local branch stays bare; only the remote uses a prefix (see § Pushing for PR).
-- **Braid strand investigation worktree** → branch `beads/<id>-<slug>` at `.worktrees/<id>-<slug>/`, where `<slug>` is a short kebab-case form of the strand title (3–5 words, lowercase).
-- **In-place sub-task branch (via `switch-task`)** → branch `beads/<id>-<slug>` *without* a corresponding `.worktrees/` directory; the branch lives wherever the caller's worktree is checked out.
+- **Braid strand investigation worktree** → branch `braid/<id>-<slug>` at `.worktrees/<id>-<slug>/`, where `<slug>` is a short kebab-case form of the strand title (3–5 words, lowercase).
+- **In-place sub-task branch (via `switch-task`)** → branch `braid/<id>-<slug>` *without* a corresponding `.worktrees/` directory; the branch lives wherever the caller's worktree is checked out.
 
 The directory mirrors the leaf of the branch name. The conventions are stable so colleagues and tooling can recognize a worktree's origin from the path alone.
 
-> **Note on the `beads/` branch prefix.** It is a *historical* git
-> namespace, kept after the braid migration because the xtask code emits
-> it and tooling/muscle-memory recognize it. It does not imply beads is
-> involved — the strand lives in the braid skein. Renaming the prefix to
-> `braid/` is a separable future cleanup (it would touch
-> `create_worktree.rs`, `switch_task.rs`, and this convention together).
+> **Note on the `braid/` branch prefix.** It is a plain git namespace —
+> the strand lives in the braid skein, and the branch name just mirrors
+> its id. It was renamed from the historical `beads/` prefix (bd-yjh1y117)
+> after the beads→braid migration; the emitter is `strand_branch()` in
+> `create_worktree.rs`, shared by `create-worktree` and `switch-task`.
+> Pre-rename branches/worktrees may still carry `beads/` locally; that is
+> harmless.
 
 ## Fresh worktree bootstrap
 
@@ -170,14 +171,14 @@ which is regenerated from the skein and never hand-edited or re-imported.
 
 ## Pushing for PR
 
-Local branch names stay bare (`issue-<N>`, `beads/<id>-<slug>`). The remote branch name uses a prefix that reflects the work type — `bugfix/`, `feature/`, etc.:
+Local branch names stay bare (`issue-<N>`, `braid/<id>-<slug>`). The remote branch name uses a prefix that reflects the work type — `bugfix/`, `feature/`, etc.:
 
 ```bash
 # GH issue, bug fix
 git push -u origin issue-<N>:bugfix/issue-<N>
 
 # Braid strand, feature work
-git push -u origin beads/<id>-<slug>:feature/<id>-<slug>
+git push -u origin braid/<id>-<slug>:feature/<id>-<slug>
 ```
 
 This keeps local branches short and consistent while remote refs are self-describing in PR lists.
@@ -188,7 +189,7 @@ If `cargo xtask create-worktree` is unavailable (fresh clone before first build,
 the xtask binary is broken on the current branch), fall back to manual setup:
 
 ```bash
-git worktree add -b beads/<id>-<slug> .worktrees/<id>-<slug> main
+git worktree add -b braid/<id>-<slug> .worktrees/<id>-<slug> main
 ```
 
 No redirect step is needed (see § Braid skein resolution above). Verify with

.claude/skills/investigate-beads/references/plan-skeleton-template.md

@@ -7,7 +7,7 @@ Copy the body below into `claude-notes/plans/YYYY-MM-DD-<slug>.md` and fill it i
 
 **Date:** YYYY-MM-DD
 **Beads:** bd-XXXX
-**Worktree:** `.worktrees/<id>-<slug>` (branch `beads/<id>-<slug>`, based on `main` @ `<short-sha>`)
+**Worktree:** `.worktrees/<id>-<slug>` (branch `braid/<id>-<slug>`, based on `main` @ `<short-sha>`)
 **Status:** Investigation — pending design alignment with user. **Do not start implementation until the user gives the go-ahead.**
 
 ## Triage verdict

.claude/skills/preview-render-parity/SKILL.md

@@ -151,10 +151,10 @@ EOF
 )"
 # braid prints the new strand id on stdout. Capture it as <id>.
 braid update <id> --status in_progress
-git switch -c beads/<id>-<short-slug>
+git switch -c braid/<id>-<short-slug>
 ```
 
-bd-kw93 is the q2-preview epic; every parity sub-strand is parent-child to it. (The git branch prefix stays `beads/` — a stable historical namespace.)
+bd-kw93 is the q2-preview epic; every parity sub-strand is parent-child to it. (The git branch prefix is `braid/` — a plain git namespace, renamed from the historical `beads/` in bd-yjh1y117.)
 
 ### Write the failing test FIRST
 
@@ -222,7 +222,7 @@ git commit -m "...(bd-<id>)"
 
 # Merge --no-ff into the integration branch
 git switch feature/q2-preview-command
-git merge --no-ff beads/<id>-<slug> -m "Merge bd-<id>: <one-line>"
+git merge --no-ff braid/<id>-<slug> -m "Merge bd-<id>: <one-line>"
 
 # Push (only after explicit user OK, per CLAUDE.md GIT PUSH POLICY)
 git push origin feature/q2-preview-command

crates/xtask/src/create_worktree.rs

@@ -107,6 +107,15 @@ pub fn validate_slug(slug: &str) -> Result<()> {
     Ok(())
 }
 
+/// Local git branch name for a braid strand's worktree / topic branch:
+/// `braid/<leaf>`, where `<leaf>` is `<id>-<slug>`. The `braid/` prefix is a
+/// plain git namespace (renamed from the historical `beads/` — bd-yjh1y117); it
+/// does not imply beads involvement. Remote refs use a work-type prefix
+/// (`bugfix/`, `feature/`) chosen at push time, not here.
+pub fn strand_branch(leaf: &str) -> String {
+    format!("braid/{leaf}")
+}
+
 #[derive(clap::Args)]
 #[command(group(clap::ArgGroup::new("mode").required(true).multiple(false)))]
 pub struct Args {
@@ -742,7 +751,7 @@ fn plan_braid(id: &str, slug_override: Option<&str>, base: &str, repo_root: &Pat
         eprintln!("note: external_ref {other:?} is not a `gh-` reference; omitting GitHub line");
     }
     Ok(Plan {
-        branch: format!("beads/{leaf}"),
+        branch: strand_branch(&leaf),
         dir: repo_root.join(".worktrees").join(&leaf),
         base: base.to_string(),
         kind: SectionKind::Braid {
@@ -1035,6 +1044,23 @@ mod tests {
         );
     }
 
+    #[test]
+    fn strand_branch_uses_the_braid_prefix() {
+        assert_eq!(
+            strand_branch("bd-abcd-some-slug"),
+            "braid/bd-abcd-some-slug"
+        );
+        let b = strand_branch("bd-x");
+        assert!(
+            b.starts_with("braid/"),
+            "strand branch must use the braid/ prefix: {b}"
+        );
+        assert!(
+            !b.starts_with("beads/"),
+            "historical beads/ prefix must be gone: {b}"
+        );
+    }
+
     #[test]
     fn repo_root_returns_absolute_directory_with_dot_git() {
         // Test runs inside this checkout, so repo_root() must succeed and

crates/xtask/src/switch_task.rs

@@ -17,7 +17,7 @@
 //! That:
 //!   1. switches the current worktree to `feature/q2-preview-command`
 //!      and runs `git pull --ff-only` so it picks up siblings' merges,
-//!   2. creates a new topic branch `beads/<id>-<slug>` off the new
+//!   2. creates a new topic branch `braid/<id>-<slug>` off the new
 //!      tip,
 //!   3. marks the braid strand `in_progress`,
 //!   4. rewrites the `<!-- BEGIN/END WORKTREE CONTEXT -->` block in
@@ -33,7 +33,7 @@ use std::process::Command;
 
 use crate::create_worktree::{
     IssueMetadata, SectionKind, build_section, derive_slug, fetch_issue_metadata,
-    parse_external_ref_to_github_url, update_claude_local_md, validate_slug,
+    parse_external_ref_to_github_url, strand_branch, update_claude_local_md, validate_slug,
 };
 
 /// Find the *current worktree's* root via `git rev-parse --show-toplevel`.
@@ -84,7 +84,7 @@ pub fn run(args: Args) -> Result<()> {
         }
         None => derive_slug(&meta.title)?,
     };
-    let branch = format!("beads/{}-{}", args.beads_id, slug);
+    let branch = strand_branch(&format!("{}-{}", args.beads_id, slug));
 
     if let Some(from) = args.from.as_deref() {
         // Best-effort fetch so origin/<from> reflects the latest tip.