fix(gui): Final Phase 7 stabilization and polish

- Resolve ImportError by correctly prefixing 'src' in modular renderers.
- Fix ImGui access violation by ensuring push_id always receives string IDs.
- Restore visible role-based background tints using layered rendering (channels).
- Definitively fix horizontal Markdown table widths by forcing group expansion.
- Centralize color management in theme_2.py and ui_shared.py.
- Standardize Files & Media inventory layout and remove legacy controls.
- Update test mocks to support modular UI and theme-driven styling.

src/ui_shared.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 from imgui_bundle import imgui
 from typing import TYPE_CHECKING, Any
+from src import imgui_scopes as imscope
 
 if TYPE_CHECKING:
     from src.gui_2 import App
@@ -20,6 +21,7 @@ C_LBL: imgui.ImVec4 = vec4(180, 180, 180)
 C_VAL: imgui.ImVec4 = vec4(220, 220, 220)
 C_KEY: imgui.ImVec4 = vec4(140, 200, 255)
 C_NUM: imgui.ImVec4 = vec4(180, 255, 180)
+C_TRM: imgui.ImVec4 = vec4(160, 160, 150) # Trimmed/Cruft
 C_SUB: imgui.ImVec4 = vec4(220, 200, 120)
 
 def render_text_viewer(app: 'App', label: str, content: str, text_type: str = 'text', force_open: bool = False, id_suffix: str = "") -> None:
@@ -30,7 +32,6 @@ def render_text_viewer(app: 'App', label: str, content: str, text_type: str = 't
   app.text_viewer_content = content
 
 def render_selectable_label(app: 'App', label: str, value: str, width: float = 0.0, multiline: bool = False, height: float = 0.0, color: Any = None) -> None:
- from src import imscope
  with imscope.id(label + str(hash(value))):
   with imscope.style_color(imgui.Col_.frame_bg, imgui.ImVec4(0, 0, 0, 0)), \
        imscope.style_var(imgui.StyleVar_.frame_border_size, 0.0):