feat: refine builder skill chip flows

docs/DESIGN_SYSTEM.md

@@ -358,6 +358,13 @@ compatible configuration controls. Large Talent pools show the selected Talent
 at rest and open their search grid through an explicit Change action. Do not
 display a prototype option that the current loadout schema cannot save.
 
+Builder cells use one leading icon track. Specializations, abilities, Skill
+Chips, and OS Protocols use registered artwork; weapons and gear use static
+category or slot fallbacks when no item artwork exists. Skill Chip slots keep
+the icon beside the set name and quality so empty and configured slots share one
+scan path. Visible builder labels stay short; full validation text remains
+available through the cell's accessible name or title.
+
 Each equipped gear or weapon Talent exposes two adjacent icon choices for Tier I
 and Tier II. Both choices reuse the Talent artwork; Tier II applies a restrained
 warm recolor so players can distinguish the pair before reading the labels.
@@ -2294,6 +2301,13 @@ active abilities, each ability has exactly three active Skill Chip definitions,
 tree rows are contiguous, at least one paid node exists, and the tree uses the
 configured available point total.
 
+The ability editor may pair the open ability with one active ability from the
+same specialization for Skill Chip sharing. Present this as an explicit optional
+relationship, exclude the current ability, and disable abilities that already
+belong to another pair. Do not infer compatibility from names or Focus
+membership. Saving either side updates the shared pair and includes it in the
+ability audit snapshot. Archiving either ability clears the pair.
+
 Compose focus identity from uploaded specialization artwork and the canonical
 Firepower, Toughness, or Engineering icon. Keep the specialization art primary
 and place the attribute mark in a smaller corner badge. Mirror ability slots 1
@@ -2641,12 +2655,17 @@ The builder presents Specialization and Focus as the first loadout decision. The
 Focus sets the primary Attribute, progression tree, and three ordered abilities.
 Its identity combines Specialization artwork and the primary Attribute mark.
 Each ability panel contains three fixed Skill Chip positions. A chip picker
-shows definitions assigned to that ability and excludes definitions assigned
-elsewhere. Skill Chips have no item-level control. The editor uses the shared
-quality profiles for direct rolls. It labels the four ability-scoped primary
-values `NOT YET DEFINED` and excludes them from current Agent and combat totals.
-Secondary capacity is Standard zero, Specialized one, Superior two, and High-end
-two; each equipped chip uses distinct selections from the shared pool.
+shows the ability's three definitions. When ISAC explicitly pairs that ability
+with one compatible ability, the picker also shows the partner's three
+definitions and labels shared entries. The relationship is bidirectional and
+does not apply to other abilities in the same specialization. Players still
+equip three chips in each ability panel. Skill Chips have no item-level control.
+The editor uses the shared quality profiles for direct rolls. It labels the four
+ability-scoped primary values `NOT YET DEFINED` and excludes them from current
+Agent and combat totals. Shared-chip primary values and 3-piece Talent outcomes
+target the ability represented by the panel. Secondary capacity is Standard
+zero, Specialized one, Superior two, and High-end two; each equipped chip uses
+distinct selections from the shared pool.
 
 The focus tree groups nodes by row and uses segmented rank controls. Disabled
 ranks remain visible with their lock state. The builder permits a row after the

docs/architecture.md

@@ -553,6 +553,24 @@ builder-ready only when each of its three assigned abilities has all three
 active Skill Chip definitions. Skill Chip mutations refresh readiness for
 focuses that reference both the previous and resulting ability.
 
+`specialization_ability_skill_chip_links` may pair two active abilities from the
+same specialization. Operators create each pair explicitly; the application does
+not infer compatibility from ability names, focus membership, or shared
+specialization. The pair is bidirectional, and an ability may belong to only one
+pair. This permits compatible abilities such as two Tactical Link variants to
+share definitions without making unrelated pairs such as two Smart Cover
+variants compatible. Archiving either ability removes the pair; restoring an
+ability does not recreate it.
+
+A linked ability can equip its own three definitions or its partner's three
+definitions, so each of its three Builder positions offers at most six choices.
+The loadout still equips three Skill Chips per ability and nine per focus.
+Ability-scoped primary values and 3-piece Talent outcomes bind to the ability
+that owns the equipped position, not the definition's original owner. Two-piece
+and 3-piece thresholds remain local to one equipped ability and never combine
+matching definitions across ability panels. ISAC audit snapshots and game-data
+transfers include the compatibility pair.
+
 Every equipped quality counts toward the two-piece threshold. After the loadout
 meets that threshold, only equipped High-end chips increase the interpolation
 step. For `h` High-end chips, where `h` is zero through three, a configured