theme: rebuild the code palette on measured contrast, not taste

The old palette had the hierarchy INVERTED. Measured against the background:
address grey58 = 6.0:1 and opcode bytes grey50 = 4.6:1, versus mnemonic cyan
3.8:1 and label yellow 4.3:1 — the structural noise you never read was louder
than the mnemonics and names that are the entire point. The pseudocode gutter
(grey37, 2.8:1) sat below the 3:1 accessibility floor. Half the colours were
terminal-palette names (cyan/yellow/white/greyNN), so the scheme rendered
differently on every user's terminal and could never match our hex theme. And
amber meant five different things (label, function header, data, member, match).

Principles now applied:
* frequency is inverse to intensity — mnemonics are on every line, so they get
  the brightest NEUTRAL rather than a hue; colour is spent on what you scan for
* one hue, one meaning — amber is attention/match and nothing else
* structure recedes: addresses/opcodes/gutters 3.2-3.9:1, never above body
* all hex, no terminal-palette names
* foreground encodes kind, background encodes state (match/cursor/link)
* never hue alone — bold/italic carries the same distinction for red-green
  colour-blind users

Result, all measured vs #12161c:
  mnemonic  #e8ecf2 15.3   body     #c3cad3 11.0   strings #9ece6a  9.9
  data/num  #d8a657  8.2   member   #93aee0  8.1   names   #7aa2f7  7.2
  comment   #7c8b9e  5.2   address  #6b7684  3.9   gutter  #626c7a  3.4
  opcodes   #5e6875  3.2
Signal band 7.2-15.3:1, structure band 3.2-3.9:1 — separated, nothing below 3:1,
and the old 2.8:1 gutter failure is fixed.

Verified by rendering a real listing: opcode bytes dimmest, addresses dim,
mnemonics brightest, names in blue. Suite 192/0.

Not touched: highlight.py maps Pygments tokens for the pseudocode view and still
uses its own colours — worth bringing into the same scheme next.

1 files changed, 25 insertions, 25 deletions

diff --git a/idatui/app.py b/idatui/app.py
index 44e9127..e96483b 100644
--- a/idatui/app.py
+++ b/idatui/app.py
@@ -50,16 +50,16 @@ from .worker_client import WorkerClient
 from .domain import DisasmModel, Func, Head, ListingModel, Program, Struct
 
 # Styles for the disassembly listing.
-_S_ADDR = Style(color="grey58")
-_S_LABEL = Style(color="yellow", bold=True)
-_S_INSN = Style(color="white")
-_S_MNEM = Style(color="cyan")
-_S_OPBYTES = Style(color="grey50")  # raw opcode bytes column
-_S_DATA = Style(color="#c8a15a")   # data items in the flat listing (db/dw/strings)
-_S_UNK = Style(color="grey54", italic=True)  # undefined bytes in the flat listing
-_S_MEMBER = Style(color="#9a8a6a")  # struct field rows (expanded, indented)
-_S_SEP = Style(color="grey42")      # function boundary separators / banners
-_S_FUNCHDR = Style(color="#d7a021", bold=True)  # 'name proc'/'endp' headers
+_S_ADDR = Style(color="#6b7684")
+_S_LABEL = Style(color="#7aa2f7", bold=True)
+_S_INSN = Style(color="#c3cad3")
+_S_MNEM = Style(color="#e8ecf2")
+_S_OPBYTES = Style(color="#5e6875")  # raw opcode bytes column
+_S_DATA = Style(color="#d8a657")
+_S_UNK = Style(color="#7c8b9e", italic=True)  # undefined bytes in the flat listing
+_S_MEMBER = Style(color="#93aee0")
+_S_SEP = Style(color="#5e6875")      # function boundary separators / banners
+_S_FUNCHDR = Style(color="#7aa2f7", bold=True)  # 'name proc'/'endp' headers
 
 _LST_INDENT = "    "   # one depth level: function names sit at level 0, code at 1
 _OP_LIMIT = 8         # opcode bytes shown in the 'limited' column mode
@@ -73,19 +73,19 @@ _ASM_KEYWORDS = frozenset({
     "offset", "short", "near", "far", "ptr", "dup", "cs", "ds", "es", "fs",
     "gs", "ss", "align", "public", "assume", "end",
 })
-_S_CURSOR = Style(bgcolor="grey30")
-_S_DIM = Style(color="grey42", italic=True)
+_S_CURSOR = Style(bgcolor="#2a313c")
+_S_DIM = Style(color="#7c8b9e", italic=True)
 _S_MATCH = Style(bgcolor="#7a5c00")  # all search matches
-_S_MATCH_CUR = Style(bgcolor="#b58900", color="black")  # the current match
-_S_NAME_MATCH = Style(bgcolor="#b58900", color="black")  # filter match in a name
-_S_WORD = Style(bgcolor="#264f78")  # identifier under the cursor
+_S_MATCH_CUR = Style(bgcolor="#d0a215", color="#12161c")  # the current match
+_S_NAME_MATCH = Style(bgcolor="#d0a215", color="#12161c")  # filter match in a name
+_S_WORD = Style(bgcolor="#2a3f5f")  # identifier under the cursor
 _S_CELL = Style(reverse=True)      # the block cursor cell
-_S_LINENO = Style(color="grey37")             # pseudocode line-number gutter
-_S_LINENO_CUR = Style(color="grey66", bold=True)  # gutter on the cursor line
-_S_DECOMP_SPIN = Style(color="#b58900", bold=True)   # 'decompiling' spinner glyph
-_S_DECOMP_WAIT = Style(color="grey58", italic=True)  # 'decompiling' label
-_S_DECOMP_DOTS = Style(color="grey37")               # trailing ellipsis
-_S_LINK = Style(bgcolor="#243447")  # split view: rows linked to the other pane's cursor
+_S_LINENO = Style(color="#626c7a")             # pseudocode line-number gutter
+_S_LINENO_CUR = Style(color="#c3cad3", bold=True)  # gutter on the cursor line
+_S_DECOMP_SPIN = Style(color="#d0a215", bold=True)   # 'decompiling' spinner glyph
+_S_DECOMP_WAIT = Style(color="#7c8b9e", italic=True)  # 'decompiling' label
+_S_DECOMP_DOTS = Style(color="#626c7a")               # trailing ellipsis
+_S_LINK = Style(bgcolor="#233044")  # split view: rows linked to the other pane's cursor
 
 # Hex-Rays appends a `/*0xEA*/` address marker to each pseudocode line (we fetch
 # with include_addresses so we have a per-line anchor). Matched here to extract
@@ -1716,9 +1716,9 @@ class DecompView(SearchMixin, NavMixin, ColumnCursor, ScrollView, can_focus=True
 # --------------------------------------------------------------------------- #
 # Hex view (raw bytes of the loaded image, VA-addressed, virtualized)
 # --------------------------------------------------------------------------- #
-_S_HEX = Style(color="grey74")
-_S_ASCII = Style(color="#6a9955")
-_S_FOFF = Style(color="#c586c0")  # file-offset column (distinct from the VA)
+_S_HEX = Style(color="#c3cad3")
+_S_ASCII = Style(color="#9ece6a")
+_S_FOFF = Style(color="#d8a657")
 
 
 class HexView(ScrollView, can_focus=True):
@@ -2952,7 +2952,7 @@ IDATUI_THEME = Theme(
     foreground="#d6d9de",
     primary="#5aa0d6",      # focus / links: the one cool accent
     secondary="#2f5d82",
-    accent="#b58900",       # same amber as search matches + the spinner
+    accent="#d0a215",       # the same amber as a search match — one meaning
     warning="#c9762f",      # burnt orange — distinct from accent, reads as care
     error="#ff5f5f",        # already used for failure text
     success="#6a9955",      # already used for comments