[FIX] web_editor: properly show snippet names via t-install directive

Since the refactoring done on ir.qweb at [1], directives are more
autonomous, so `t-att`, `t-options`, etc are no longer evaluated by
other directives. These directives are also ordered.

Before this commit, when directives such as `t-snippet`, `t-install`,
etc were called, the other attributes had already been consumed. Indeed,
at the end of the compilation, tags should no longer have attributes,
`t-att` removes all statics ones. So relying on the `string` attribute
in `t-install` was broken and so the snippet names for the snippets to
install from the editor panel in edit mode were gone.

This commit fixes that by evaluating those specific directives earlier.

[1]: https://github.com/odoo/odoo/commit/e830953570d5f28aee9bdcdf97af18d3e3246030



task-2762377

closes odoo/odoo#84752

X-original-commit: f40b9522f20d5fbfe62c3718566c1d92ccfad75b
Signed-off-by: Quentin Smetz (qsm) <qsm@odoo.com>

addons/web_editor/models/ir_qweb.py

@@ -120,10 +120,13 @@ class IrQWeb(models.AbstractModel):
 
     def _directives_eval_order(self):
         directives = super()._directives_eval_order()
-        directives.insert(directives.index('att'), 'placeholder')
-        directives.insert(directives.index('call'), 'snippet')
-        directives.insert(directives.index('call'), 'snippet-call')
-        directives.insert(directives.index('call'), 'install')
+        # Insert before "att" as those may rely on static attributes like
+        # "string" and "att" clears all of those
+        index = directives.index('att') - 1
+        directives.insert(index, 'placeholder')
+        directives.insert(index, 'snippet')
+        directives.insert(index, 'snippet-call')
+        directives.insert(index, 'install')
         return directives