tcl: tick Phase 1 tokenizer, add progress log entry

plans/tcl-on-sx.md

@@ -50,7 +50,7 @@ Core mapping:
 ## Roadmap
 
 ### Phase 1 — tokenizer + parser (the Dodekalogue)
-- [ ] Tokenizer applying the 12 rules:
+- [x] Tokenizer applying the 12 rules:
   1. Commands separated by `;` or newlines
   2. Words separated by whitespace within a command
   3. Double-quoted words: `\` escapes + `[…]` + `${…}` + `$var` substitution
@@ -120,7 +120,7 @@ Core mapping:
 
 _Newest first._
 
-- _(none yet)_
+- 2026-04-25: Phase 1 tokenizer (Dodekalogue) — `lib/tcl/tokenizer.sx`, 52 tests green, commit 666e29d5
 
 ## Blockers