chore(vendor): import pi 0.85.1

Imported as a linear vendor commit so forge rebases do not replay the upstream root tree.

git-subtree-dir: third_party/pi

git-subtree-split: d981de1229ef899957bbe968bc8dcda02a21f477

third_party/pi/.github/ISSUE_TEMPLATE/bug.yml

@@ -0,0 +1,45 @@
+name: Bug Report
+description: Report something that's broken
+labels: ["bug"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        **Before you start:** Read [CONTRIBUTING.md](https://github.com/earendil-works/pi/blob/main/CONTRIBUTING.md).
+
+        New issues from new contributors are auto-closed by default. Maintainers review auto-closed issues daily. Issues that do not meet the quality bar in [CONTRIBUTING.md](https://github.com/earendil-works/pi/blob/main/CONTRIBUTING.md) will not be reopened or receive a reply.
+
+        Keep this short. If it doesn't fit on one screen, it's too long. Write in your own voice.
+
+        **Important:** before reporting an issue in core, please validate first with `pi -ne` that this is not caused by an extension you loaded.
+
+  - type: textarea
+    id: description
+    attributes:
+      label: What happened?
+      description: Be specific. Include error messages if any.
+    validations:
+      required: true
+
+  - type: textarea
+    id: repro
+    attributes:
+      label: Steps to reproduce
+      description: Minimal steps to trigger the bug.
+    validations:
+      required: true
+
+  - type: textarea
+    id: expected
+    attributes:
+      label: Expected behavior
+    validations:
+      required: false
+
+  - type: input
+    id: version
+    attributes:
+      label: Version
+      description: e.g. 0.49.0
+    validations:
+      required: false

third_party/pi/.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,5 @@
+blank_issues_enabled: false
+contact_links:
+  - name: Questions
+    url: https://discord.com/invite/3cU7Bz4UPx
+    about: Ask questions on Discord instead of opening an issue

third_party/pi/.github/ISSUE_TEMPLATE/contribution.yml

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+name: Contribution Proposal
+description: Propose a change or feature (required for new contributors before submitting a PR)
+labels: []
+body:
+  - type: markdown
+    attributes:
+      value: |
+        **Before you start:** Read [CONTRIBUTING.md](https://github.com/earendil-works/pi/blob/main/CONTRIBUTING.md).
+
+        New issues from new contributors are auto-closed by default. Maintainers review auto-closed issues daily. Issues that do not meet the quality bar in [CONTRIBUTING.md](https://github.com/earendil-works/pi/blob/main/CONTRIBUTING.md) will not be reopened or receive a reply.
+
+        Keep this short. If it doesn't fit on one screen, it's too long. Write in your own voice.
+
+  - type: textarea
+    id: what
+    attributes:
+      label: What do you want to change?
+      description: Be specific and concise.
+    validations:
+      required: true
+
+  - type: textarea
+    id: why
+    attributes:
+      label: Why?
+      description: What problem does this solve?
+    validations:
+      required: true
+
+  - type: textarea
+    id: how
+    attributes:
+      label: How? (optional)
+      description: Brief technical approach if you have one in mind.
+    validations:
+      required: false

third_party/pi/.github/ISSUE_TEMPLATE/package-report.yml

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+name: Package Report
+description: Report a problematic Pi package listed on pi.dev
+labels: ["package-report"]
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Use this form to report a package listed on pi.dev. For Pi core bugs, use the bug report template instead.
+
+        New issues from new contributors are auto-closed by default. Maintainers review auto-closed issues daily. Issues that do not meet the quality bar in [CONTRIBUTING.md](https://github.com/earendil-works/pi/blob/main/CONTRIBUTING.md) will not be reopened or receive a reply.
+
+        Keep this short. If it doesn't fit on one screen, it's too long. Write in your own voice.
+
+  - type: input
+    id: package-name
+    attributes:
+      label: Package name
+      description: The npm package name from pi.dev.
+      placeholder: "@scope/package"
+    validations:
+      required: true
+
+  - type: input
+    id: package-version
+    attributes:
+      label: Version
+      description: The package version shown on pi.dev.
+      placeholder: "0.1.0"
+    validations:
+      required: false
+
+  - type: dropdown
+    id: report-type
+    attributes:
+      label: What are you reporting?
+      options:
+        - Malicious or unsafe behavior
+        - Impersonation
+        - Trademark / TOS Violations
+    validations:
+      required: true
+
+  - type: textarea
+    id: details
+    attributes:
+      label: Details
+      description: Describe the concern and include links, logs, or screenshots if helpful.
+    validations:
+      required: true