SEAM — Mature Terminal Identity
================================
Phase: mature (2026-04-20)
Replaces: conception-phase retro/phosphor palette (assets/retro-preview-*)

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S MARK  (4 rows, box-drawing, cyan/violet alternating)
─────────────────────────────────────────────────────────────────────────────

   ╭──────╮
╭──╯ ╭──╮ ╰──╮
╰──╮ ╰──╯ ╭──╯
   ╰──────╯

Colors:
  Row 0 (top arc)     → CYAN    #7fe0ff
  Row 1 (upper body)  → VIOLET  #9b6cff
  Row 2 (lower body)  → CYAN    #7fe0ff
  Row 3 (bottom arc)  → VIOLET  #9b6cff

─────────────────────────────────────────────────────────────────────────────
SEAM WORDMARK  (6 rows figlet, CYAN_BRIGHT #8df6ff — first 4 rows in header)
─────────────────────────────────────────────────────────────────────────────

███████╗███████╗ █████╗ ███╗   ███╗
██╔════╝██╔════╝██╔══██╗████╗ ████║
███████╗█████╗  ███████║██╔████╔██║
╚════██║██╔══╝  ██╔══██║██║╚██╔╝██║
███████║███████╗██║  ██║██║ ╚═╝ ██║
╚══════╝╚══════╝╚═╝  ╚═╝╚═╝     ╚═╝

─────────────────────────────────────────────────────────────────────────────
DASHBOARD HEADER LAYOUT  (4 content rows, height: 6 in Textual CSS)
─────────────────────────────────────────────────────────────────────────────

   ╭──────╮    ███████╗███████╗ █████╗ ███╗   ███╗   :: SEAM :: v0.1.0 :: MIRL Interpreter & Persistence Engine ::
╭──╯ ╭──╮ ╰──╮ ██╔════╝██╔════╝██╔══██╗████╗ ████║   Launched from: <launch_dir>
╰──╮ ╰──╯ ╭──╯ ███████╗█████╗  ███████║██╔████╔██║   Shell cwd:     <shell_cwd>
   ╰──────╯    ╚════██║██╔══╝  ██╔══██║██║╚██╔╝██║   Model: <model> (<status>)   Mode: <mode>

─────────────────────────────────────────────────────────────────────────────
NOTES
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• Implemented in: seam_runtime/ui/logo.py → _BOX_LOGO / _BOX_SEAM / render_header()
• Wired into:     seam_runtime/dashboard.py → _refresh_logo() → #logo-header Static
• Preview:        python -m seam_runtime.ui.logo --header  (requires UTF-8 terminal)
• Background:     BG_DEEP #050b1e (dashboard chrome)
• Border:         round #4f8cfb (BLUE)
• The conception-phase retro/amber-phosphor palette is retired.
  Those assets remain in branding/assets/ for historical reference.
