Improve incident-postmortem skill: Google SRE format, fishbone + 5 Whys, multiple output formats 🤖🤖🤖

docs/README.skills.md

@@ -243,7 +243,7 @@ See [CONTRIBUTING.md](../CONTRIBUTING.md#adding-skills) for guidelines on how to
 | [image-manipulation-image-magick](../skills/image-manipulation-image-magick/SKILL.md)<br />`gh skills install github/awesome-copilot image-manipulation-image-magick` | Process and manipulate images using ImageMagick. Supports resizing, format conversion, batch processing, and retrieving image metadata. Use when working with images, creating thumbnails, resizing wallpapers, or performing batch image operations. | None |
 | [impediment-prioritization](../skills/impediment-prioritization/SKILL.md)<br />`gh skills install github/awesome-copilot impediment-prioritization` | Ranks any list of impediments and their countermeasures using a value-stream scoring model (ROI, Cost to Implement, Ease of Deployment, Risk Factor) and a fixed prioritization formula. Use when someone asks to prioritize, rank, sequence, or triage impediments, countermeasures, remediation items, risks, findings, gaps, action items, or backlog entries; or mentions value-stream prioritization, A3 / lean countermeasure ranking, ROI vs. effort scoring, or building a remediation / improvement backlog. Works with GHQR findings, audit results, retrospective action items, risk registers, architecture review gaps, or any free-form `{impediment, countermeasure}` list. | `references/scoring-rubric.md` |
 | [import-infrastructure-as-code](../skills/import-infrastructure-as-code/SKILL.md)<br />`gh skills install github/awesome-copilot import-infrastructure-as-code` | Import existing Azure resources into Terraform using Azure CLI discovery and Azure Verified Modules (AVM). Use when asked to reverse-engineer live Azure infrastructure, generate Infrastructure as Code from existing subscriptions/resource groups/resource IDs, map dependencies, derive exact import addresses from downloaded module source, prevent configuration drift, and produce AVM-based Terraform files ready for validation and planning across any Azure resource type. | None |
-| [incident-postmortem](../skills/incident-postmortem/SKILL.md)<br />`gh skills install github/awesome-copilot incident-postmortem` | Use when an outage, production incident, or significant service degradation has occurred and the team needs to write a structured blameless post-mortem. Triggers on phrases like "write a post-mortem", "incident review", "what went wrong", "outage report", "root cause analysis", or "RCA". Covers timeline reconstruction, contributing factor analysis, impact quantification, and action item generation with owners. | None |
+| [incident-postmortem](../skills/incident-postmortem/SKILL.md)<br />`gh skills install github/awesome-copilot incident-postmortem` | Use when an outage, production incident, or significant service degradation has occurred and the team needs a blameless post-mortem / RCA document in the Google SRE format. Triggers on phrases like "write a post-mortem", "incident review", "what went wrong", "outage report", "root cause analysis", "RCA", or "fishbone". Collects incident inputs from the user, uses a fishbone (Ishikawa) diagram to surface candidate causes, drills the strongest branches with 5 Whys, and produces typed action items. Outputs Markdown by default, with HTML, DOCX, or PDF on request. | `references/fishbone-example.md`<br />`references/postmortem-template.md` |
 | [integrate-context-matic](../skills/integrate-context-matic/SKILL.md)<br />`gh skills install github/awesome-copilot integrate-context-matic` | Discovers and integrates third-party APIs using the context-matic MCP server. Uses `fetch_api` to find available API SDKs, `ask` for integration guidance, `model_search` and `endpoint_search` for SDK details. Use when the user asks to integrate a third-party API, add an API client, implement features with an external API, or work with any third-party API or SDK. | None |
 | [issue-fields-migration](../skills/issue-fields-migration/SKILL.md)<br />`gh skills install github/awesome-copilot issue-fields-migration` | Bulk-migrate metadata to GitHub issue fields from two sources: repo labels (e.g. priority labels to a Priority field) and Project V2 fields. Use when users say "migrate my labels to issue fields", "migrate project fields to issue fields", "convert labels to issue fields", "copy project field values to issue fields", or ask about adopting issue fields. Issue fields are org-level typed metadata (single select, text, number, date) that replace label-based workarounds with structured, searchable, cross-repo fields. | `references/issue-fields-api.md`<br />`references/labels-api.md`<br />`references/projects-api.md` |
 | [java-add-graalvm-native-image-support](../skills/java-add-graalvm-native-image-support/SKILL.md)<br />`gh skills install github/awesome-copilot java-add-graalvm-native-image-support` | GraalVM Native Image skill for Spring Boot, Micronaut and plain Java: detects the build tool and framework, adds native image support, builds the executable, analyzes errors, and iterates until the native build succeeds and the binary runs correctly. For Quarkus projects it only dispatches to the quarkus-native-and-container skill. | `references/build-tools.md`<br />`references/micronaut.md`<br />`references/quarkus.md`<br />`references/reachability-metadata.md`<br />`references/spring-boot.md`<br />`references/troubleshooting.md` |