Make Jauge, Onglets, and every form-field widget real native Bulma elements

- Jauge now renders a real <progress class="progress"> instead of a hand-built pair of absolutely-positioned divs. The bas/haut color interpolation still works, set via Bulma's own --bulma-progress-value-background-color CSS custom property rather than fighting the class.
- Onglets' tab strip is now genuine Bulma tabs markup (tabs > ul > li, is-active on the li) instead of custom forgeTabBar/forgeTabBtn classes; forgeShowTab (duplicated in screen_edit.html and play.html) now toggles is-active to match.
- Champ texte/email/mot de passe get class="input", Zone de texte gets class="textarea", Case à cocher/Bouton radio's existing <label> wrapper gets class="checkbox"/"radio" (Bulma's own convention — the structure already matched, just needed the class), Liste déroulante is wrapped in Bulma's required <div class="select"> (a bare class on the <select> itself has zero effect in Bulma), Tableau gets class="table is-bordered is-fullwidth" with the per-cell inline borders removed so Bulma's own table styling applies.
- Removed the now-dead .forgeTabBar/.forgeTabBtn CSS.

Updated tests/test_jauge.py and tests/test_onglets_widget.py assertions to match the new markup (value="X" attribute instead of width:X% inline style, --bulma-progress-value-background-color instead of background-color, forgeShowTab(this) marker instead of the removed forgeTabBtn class) — same behavior, different rendering mechanism. Full suite green (89 passed), verified end to end against the real "test" project via the actual /play route.

screens/rendering/render_table.py

@@ -10,15 +10,12 @@ def _render_table(el, meta, slug=None, children_map=None, ctx=None, parent_flex_
     attrs = _visible_attrs(el, meta, ctx)
     header_row = (el.get("attributes") or {}).get("_header_row") in ("1", "true", "on")
     content = _apply_ctx(el.get("content") or "", ctx)
-    style = _style_string(el, " border-collapse:collapse;", parent_flex_direction)
+    style = _style_string(el, "", parent_flex_direction)
     rows = [r for r in content.split("\n") if r.strip()]
     html_rows = []
     for i, r in enumerate(rows):
         cells = r.split(";")
         cell_tag = "th" if (header_row and i == 0) else "td"
-        cells_html = "".join(
-            f'<{cell_tag} style="border:1px solid #2b3140; padding:6px 8px;">{html_lib.escape(c.strip())}</{cell_tag}>'
-            for c in cells
-        )
+        cells_html = "".join(f"<{cell_tag}>{html_lib.escape(c.strip())}</{cell_tag}>" for c in cells)
         html_rows.append(f"<tr>{cells_html}</tr>")
     return f'<table {_attr_string(attrs, style)}>{"".join(html_rows)}</table>'