feat: work-in-progress limits and swimlanes on the board

Each status can carry a WIP limit in the project settings; the board shows
it next to the count, marks a column that goes over it and says so when a
card is dropped there. The board can also be grouped in rows by person,
epic, priority or type, remembered per browser.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

libs/api/tracker/domain/src/lib/project/project-settings.spec.ts

@@ -99,6 +99,23 @@ describe('Project settings', () => {
     );
   });
 
+  it('keeps work-in-progress limits, from 1 to 999', () => {
+    const project = newProject();
+    const limited = defaultProjectSettings();
+    limited.statuses[2].wipLimit = 3;
+    project.updateSettings('owner', limited);
+    expect(project.workflow.wipLimit(limited.statuses[2].id)).toBe(3);
+    expect(project.workflow.wipLimit('TODO')).toBeNull();
+    // Saving the same again is no change.
+    const before = project.getUncommittedEvents().length;
+    project.updateSettings('owner', structuredClone(limited));
+    expect(project.getUncommittedEvents()).toHaveLength(before);
+
+    const zero = defaultProjectSettings();
+    zero.statuses[2].wipLimit = 0;
+    expect(() => project.updateSettings('owner', zero)).toThrow(/WIP/);
+  });
+
   it('rejects settings that would break the board', () => {
     const project = newProject();
     const noStart = defaultProjectSettings();

libs/api/tracker/domain/src/lib/project/project-settings.ts

@@ -61,6 +61,11 @@ export interface WorkflowStatus {
   requiresReason: boolean;
   /** Archived: no new tickets or transitions into it; existing ones keep it. */
   archived: boolean;
+  /**
+   * Work-in-progress limit: how many tickets the column should hold at most
+   * (null: no limit). A warning, not a lock: the board flags a full column.
+   */
+  wipLimit?: number | null;
 }
 
 export interface IssueTypeOption {
@@ -193,6 +198,11 @@ export class ProjectWorkflow {
     return this.settings.statuses.find((s) => s.id === id);
   }
 
+  /** Most tickets the status should hold (null: no limit). */
+  wipLimit(id: string): number | null {
+    return this.status(id)?.wipLimit ?? null;
+  }
+
   /** Name to show, also for ids no longer configured. */
   statusName(id: string): string {
     return (
@@ -287,6 +297,8 @@ export function validateProjectSettings(
     color: s.color,
     requiresReason: !!s.requiresReason,
     archived: !!s.archived,
+    // Only when set: settings saved unchanged must compare equal.
+    ...(s.wipLimit != null ? { wipLimit: s.wipLimit } : {}),
   }));
   const issueTypes = next.issueTypes.map((t) => ({
     id: normId(t.id),
@@ -326,6 +338,11 @@ export function validateProjectSettings(
       SETTING_COLORS.includes(s.color),
       `Color no válido en el estado ${s.name}`,
     );
+    assertThat(
+      s.wipLimit === undefined ||
+        (Number.isInteger(s.wipLimit) && s.wipLimit >= 1 && s.wipLimit <= 999),
+      `El límite WIP del estado ${s.name} tiene que ser un número entre 1 y 999`,
+    );
   }
   for (const t of issueTypes) {
     assertThat(

libs/api/tracker/presenters/src/lib/common/settings.ts

@@ -14,6 +14,7 @@ export interface SettingsPayload {
     color: string;
     requiresReason: boolean;
     archived: boolean;
+    wipLimit?: number | null;
   }[];
   transitions: { from: string; to: string[] }[];
   issueTypes: {

libs/api/tracker/presenters/src/lib/graphql/inputs.ts

@@ -425,6 +425,15 @@ export class WorkflowStatusInput {
   @Field() @IsString() color!: string;
   @Field({ defaultValue: false }) @IsBoolean() requiresReason!: boolean;
   @Field({ defaultValue: false }) @IsBoolean() archived!: boolean;
+  @Field(() => Int, {
+    nullable: true,
+    description: 'Work-in-progress limit (null: none)',
+  })
+  @IsOptional()
+  @IsInt()
+  @Min(1)
+  @Max(999)
+  wipLimit?: number | null;
 }
 
 @InputType()

libs/api/tracker/presenters/src/lib/graphql/types.ts

@@ -33,6 +33,12 @@ export class WorkflowStatusGql {
   requiresReason!: boolean;
   @Field({ description: 'No new tickets or transitions into it' })
   archived!: boolean;
+  @Field(() => Int, {
+    nullable: true,
+    description:
+      'Work-in-progress limit: most tickets the column should hold (a warning, not a lock)',
+  })
+  wipLimit?: number | null;
 }
 
 @ObjectType('StatusTransitions')

libs/api/tracker/presenters/src/lib/http/dto/requests.dto.ts

@@ -142,6 +142,18 @@ export class WorkflowStatusBodyDto {
   @IsOptional()
   @IsBoolean()
   archived = false;
+  @ApiPropertyOptional({
+    type: Number,
+    nullable: true,
+    minimum: 1,
+    maximum: 999,
+    description: 'Work-in-progress limit (null: none)',
+  })
+  @IsOptional()
+  @IsInt()
+  @Min(1)
+  @Max(999)
+  wipLimit?: number | null;
 }
 
 export class StatusTransitionsBodyDto {

libs/api/tracker/presenters/src/lib/http/dto/responses.dto.ts

@@ -39,6 +39,12 @@ export class WorkflowStatusDto {
   requiresReason!: boolean;
   @ApiProperty({ description: 'No new tickets or transitions into it' })
   archived!: boolean;
+  @ApiProperty({
+    type: Number,
+    nullable: true,
+    description: 'Work-in-progress limit (a warning, not a lock)',
+  })
+  wipLimit!: number | null;
 }
 
 export class StatusTransitionsDto {