Add help target, colorize output, and improve release workflow

- Add colored terminal output support (GREEN, YELLOW, BLUE, NC)
- Introduce `help` target to document all Makefile targets
- Enhance `bump-version` to accept VERSION env var for manual version setting
- Refactor jjpush: split into modular targets (jjpush-notes, jjpush-push, jjpush-tag)
- Replace orla with aichat for AI-powered release notes generation
- Add robust JSON parsing using Python for release notes extraction
- Use stakk for PR submission (replacing raw `jj git push`)
- Generate and store release notes in temp files for tag creation
- Add installation instructions to release tags
- Update .PHONY with new targets

4.4.20: Rope-based parsing, improved release tooling, and bug fixes

### Enhancements
- **Rope-based parsing**: Added direct rope parsing for FASTA, EMBL, and FASTQ formats via `FastaChunkParserRope`, `EmblChunkParserRope`, and `FastqChunkRope` functions, eliminating unnecessary memory allocation via Pack(). Sequence extraction now supports U→T conversion and improved line ending detection.
- **Rope scanner refactoring**: Unified rope scanning logic under a new `ropeScanner`, improving maintainability and consistency across parsers.
- **Sequence handling**: Added `TakeQualities()` method to BioSequence for more efficient quality data handling.

### Bug Fixes
- **Compression behavior**: Fixed CompressStream to correctly use the `compressed` variable instead of a hardcoded boolean.
- **String splitting**: Replaced ambiguous `SplitInTwo` calls with precise `LeftSplitInTwo` or `RightSplitInTwo`, and added dedicated right-split utility.

### Tooling & Workflow Improvements
- **Makefile enhancements**: Added colored terminal output, a `help` target for documenting all targets, and improved release workflow automation.
- **Release process**: Refactored `jjpush` into modular targets (`jjpush-notes`, `jjpush-push`, `jjpush-tag`), replaced `orla` with `aichat` for AI-assisted release notes, and introduced robust JSON parsing using Python. Release notes are now generated and stored in temp files for tag creation.
- **Versioning**: `bump-version` now supports the VERSION environment variable for manual version setting.
- **Submission**: Switched from raw `jj git push` to `stakk` for PR submission.

### Internal Notes
- Installation instructions are now included in release tags.
- Fixed-size carry buffer replaced with dynamic slice for arbitrarily long line support without extra allocations.

tools/json2md.py

@@ -0,0 +1,36 @@
+#!/usr/bin/env python3
+"""
+Read potentially malformed JSON from stdin (aichat output), extract title and
+body, and print them as plain text: title on first line, blank line, then body.
+Exits with 1 on failure (no output).
+"""
+
+import sys
+import json
+import re
+
+text = sys.stdin.read()
+
+m = re.search(r'\{.*\}', text, re.DOTALL)
+if not m:
+    sys.exit(1)
+
+s = m.group()
+obj = None
+
+try:
+    obj = json.loads(s)
+except Exception:
+    s2 = re.sub(r'(?<!\\)\n', r'\\n', s)
+    try:
+        obj = json.loads(s2)
+    except Exception:
+        sys.exit(1)
+
+title = obj.get('title', '').strip()
+body  = obj.get('body', '').strip()
+
+if not title or not body:
+    sys.exit(1)
+
+print(f"{title}\n\n{body}")