feat(declare)!: parse role=declare blocks as YAML

Replace the tag/threshold/key/expr CSV body with YAML `vars:` and
`tags:` maps. `parseDeclare` validates the body with an exported Zod
schema and returns the same declaration and modifier shapes the
reactivity engine already consumes.

The breaking rename from `parseDeclareCsv` updates the registry, the
journal re-exports, and the `tttk check` role checks, where R003 now
reports schema errors with their path and R004 warns when a block
declares nothing.

src/cli/validate/known.ts

@@ -232,12 +232,12 @@ export const ROLE_SPECS: readonly RoleSpec[] = [
   },
   {
     role: "declare",
-    info: "csv role=declare",
+    info: "yaml role=declare",
     summary: "Reactive variable / tag-modifier definitions.",
     details:
-      "Columns (any order): `tag`, `threshold`, `key`, `expr`. A row with an empty `tag` declares a variable; a row with a `#tag` applies a modifier when that tag is active.",
+      "YAML with two optional maps. `vars:` maps a `$name` to its expression. `tags:` maps a tag name to a map of thresholds to `$target` modifiers: at that tag count the target gains the value, so sibling thresholds stack. Tag names may be written with or without the leading `#`. YAML resolves bare numbers to numbers and everything else to strings; both become expression text.",
     examples: [
-      "```csv role=declare\ntag,threshold,key,expr\n,,$hp,$con*5+$mod_hp\n#warrior,2,$mod_hp,20\n```",
+      "```yaml role=declare\nvars:\n  $hp: $con*5 + $mod_hp\n  $ac: 10 + $dex\ntags:\n  warrior:\n    1:\n      $mod_hp: 20\n    2:\n      $mod_str: 1\n```",
     ],
   },
   {