refactor(harness): renaming prodotto tht (Onda -1)

Thoth (tht) è il prodotto, PSD è il cliente. Nessun riferimento al contesto
clinico nel codice.

Rinomine:
- comando+package nsp→tht (dir nsp/→tht/, 46 import, pyproject entry point)
- gate nsp-gate.js→tht-gate.js (+ rewrite token, relayIfNspFails→relayIfThtFails)
- workspace chirone.{example,test}.yaml→tht.{example,test}.yaml (generici)
- env THOTH_→THT_ (19 var) + NSP_ stragglers (NSP_HARNESS_ROOT, NSP_SESSION)
- commenti/docstring chirone/psdwp3/policlinico neutralizzati ('the reference
  implementation', 'the DWH')

Aggiunto [tool.setuptools.packages.find] include=['tht*'] (necessario: l'auto-
discovery rompeva con tht/ + workspaces/ come top-level multipli).

.env operatore aggiornato in-place (prefissi THT_, valori preservati, gitignored).

Verifica: pytest 109 passed, npm test 14 pass, tht phase meta --json OK, zero
residui nsp/THOTH_/NSP_/chirone nel package.

harness/tht/cli/__init__.py

@@ -0,0 +1,41 @@
+"""tht CLI -- Typer app `tht`.
+
+Minimal skeleton for now: registers `phase_app` (the gate needs `tht phase meta --json`).
+Other command groups (db, schema, lsh, vector, memory, session, decision, sql, cte,
+evidence, search) are wired in their porting tasks, once their backend deps land
+(A9 ports db/mschema/_guards; B1 ports vectorstore; B3 ports search/lshindex/sampling).
+"""
+from __future__ import annotations
+
+import typer
+
+from tht import __version__
+
+app = typer.Typer(
+    help="tht (Thoth) -- kit operativo per generazione SQL assistito da Pi",
+    no_args_is_help=True,
+)
+
+
+def _version_callback(value: bool) -> None:
+    if value:
+        typer.echo(__version__)
+        raise typer.Exit()
+
+
+@app.callback()
+def main(
+    version: bool = typer.Option(
+        False,
+        "--version",
+        callback=_version_callback,
+        is_eager=True,
+        help="Mostra la versione ed esce.",
+    ),
+) -> None:
+    pass
+
+
+from tht.cli.phase_cmd import phase_app  # noqa: E402
+
+app.add_typer(phase_app, name="phase")