Add GitHub issue pipelines and prompts using gh CLI

gh-issue-impl, gh-issue-research, gh-issue-rewrite, gh-issue-update
pipelines with corresponding prompts for fetch-assess, plan,
implement, and create-pr steps.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.wave/prompts/speckit-flow/clarify.md

@@ -0,0 +1,42 @@
+You are refining a feature specification by identifying and resolving ambiguities.
+
+Feature context: {{ input }}
+
+## Working Directory
+
+You are running in an **isolated git worktree** shared with previous pipeline steps.
+Your working directory IS the project root. The feature branch was created by a
+previous step and is already checked out.
+
+## Instructions
+
+Follow the `/speckit.clarify` workflow:
+
+1. Find the feature directory and spec file path from the spec info artifact
+2. Run `.specify/scripts/bash/check-prerequisites.sh --json --paths-only` to confirm paths
+3. Load the current spec and perform a focused ambiguity scan across:
+   - Functional scope and domain model
+   - Integration points and edge cases
+   - Terminology consistency
+4. Generate up to 5 clarification questions (prioritized)
+5. For each question, select the best option based on codebase context
+6. Integrate each resolution directly into the spec file
+7. Save the updated spec
+
+## CONSTRAINTS
+
+- Do NOT spawn Task subagents — work directly in the main context
+- Do NOT use WebSearch — all clarifications should be resolved from codebase
+  context and the existing spec. The specify step already did the research.
+- Keep the scope tight: only fix genuine ambiguities, don't redesign the spec
+
+## Non-Interactive Mode
+
+Since this runs in a pipeline, resolve all clarifications autonomously:
+- Select the recommended option based on codebase patterns and existing architecture
+- Document the rationale for each choice in the Clarifications section
+- Err on the side of commonly-accepted industry standards
+
+## Output
+
+Produce a JSON status report matching the injected output schema.