fleetd #393: deliver memberSkills to opencode members, and stop overclaiming seeding success

GitWorktrees.seedSkills copies memberSkills:-seeded skill folders into every
provisioned worktree's .claude/skills/ and logged "skill seeding: N of M" as
if that were success — but .claude/skills/ is a Claude Code CLI convention.
opencode has no such discovery, so a kind: opencode member never actually
read a seeded skill even though the log said N of M succeeded.

Two changes, both required:

1. Deliver it. OpenCodeLauncher.skillInstructionFiles scans
   <cwd>/.claude/skills/*/SKILL.md at spawn time (the one point the launcher
   knows both the kind and the cwd) and appends each to the generated
   opencode.json's instructions[] array, the same channel already used for
   the member charter and IDE rules. A skill folder with no SKILL.md is
   named and skipped rather than silently dropped.

2. Stop claiming it where the claim can't be verified. GitWorktrees.seedSkills'
   log now says explicitly that consumption depends on the member's kind and
   points at the launcher's own log; OpenCodeLauncher logs its own kind-aware
   "skill delivery: M of N ..." line once the kind is actually known, naming
   any folder it could not turn into an instructions[] entry.

fleetd.example.yaml's memberSkills: doc previously claimed "Claude Code
members only; an opencode member reads a different path (.opencode/agent)
this key does not touch" — false as of this fix, corrected to name both
kinds and how each consumes it.

Tests: OpenCodeLauncherTest gains two cases driving the real
GitWorktrees#add seeding path (not a hand-built fixture) into an
opencode-kind spawn — one asserting a seeded skill's SKILL.md lands in
instructions[] plus the honest log line, one covering a skill folder
without SKILL.md (delivered skills still flow, the malformed one is named
in the log and excluded from instructions[]). ClaudeCodeLauncher is
untouched — its native .claude/skills/ discovery already worked and is out
of scope.

mvn -B clean test: Tests run: 1603, Failures: 0, Errors: 0, Skipped: 0 — BUILD SUCCESS

fleetd/fleetd.example.yaml

@@ -793,12 +793,21 @@ guard:
 # .claude/skills/, so a member spawned against ANY repo — not only one that already ships its own
 # copy — can load a bridge skill (e.g. implementer). Unset (the default): no worktree is touched
 # beyond today's behaviour. A skill folder the target repo already carries under
-# .claude/skills/<name> is never overwritten — the repo's own copy always wins. Claude Code
-# members only; an opencode member reads a different path (.opencode/agent) this key does not
-# touch. Best-effort like worktreeGroup above: a missing/unreadable directory here is logged and
-# skipped, never a failed spawn. Every non-hidden subdirectory of this directory is copied
-# wholesale, with no per-file allowlist — don't park scratch files or drafts alongside the real
-# skill folders, they will be copied into every provisioned worktree too.
+# .claude/skills/<name> is never overwritten — the repo's own copy always wins. Best-effort like
+# worktreeGroup above: a missing/unreadable directory here is logged and skipped, never a failed
+# spawn. Every non-hidden subdirectory of this directory is copied wholesale, with no per-file
+# allowlist — don't park scratch files or drafts alongside the real skill folders, they will be
+# copied into every provisioned worktree too.
+#
+# fleetd #393: which member KINDS actually consume this once it is copied. kind: claude-code —
+# the Claude Code CLI discovers .claude/skills/ on its own; nothing else is needed. kind: opencode
+# — opencode has no such discovery, so OpenCodeLauncher reads whatever landed under
+# .claude/skills/ and appends each seeded skill's SKILL.md to the generated instructions[] file
+# (opencode's only channel for static guidance text; unlike Claude Code's Skill tool, the content
+# is always part of the system prompt, not loaded on demand). Both kinds are covered as of #393 —
+# earlier builds copied the files for every kind but only claude-code could read them, and the
+# seeding log said "N of M" regardless. Check the per-spawn launcher log (not just the seeding
+# log) to see what a given member actually got.
 # memberSkills: /path/to/fleetd/checkout/.claude/skills
 
 # Session lifecycle limits (CB-303). All knobs are opt-in; omit or set to null to keep