…ts (elastic#265724)

Resolves 3 `@elastic/eui/callout-announce-on-mount` lint violations in
`@elastic/kibana-presentation` files to ensure conditionally rendered
callouts are properly handled by screen readers.

- **`project_picker_content.tsx`** — `announceOnMount` (true): error
callout appears dynamically after a failed fetch
- **`project_picker.tsx`** — `announceOnMount={false}`: readonly callout
is a static prop-based condition
- **`datasource_component.js`** — `announceOnMount={false}`: expression
args warning is a static data-shape condition

- [x] Added label `a11y:agent-pr`
- [x] Fixed all listed files

> [!WARNING]
>
> <details>
> <summary>Firewall rules blocked me from connecting to one or more
addresses (expand for details)</summary>
>
> #### I tried to connect to the following addresses, but was blocked by
firewall rules:
>
> - `ci-stats.kibana.dev`
> - Triggering command:
`/home/REDACTED/.nvm/versions/node/v24.14.1/bin/node
/home/REDACTED/.nvm/versions/node/v24.14.1/bin/node
scripts/yarn_install_scripts.js run ldd 0.8.2` (dns block)
> - Triggering command:
`/home/REDACTED/.nvm/versions/node/v24.14.1/bin/node
/home/REDACTED/.nvm/versions/node/v24.14.1/bin/node scripts/kbn
bootstrap` (dns block)
> - Triggering command:
`/home/REDACTED/.nvm/versions/node/v24.14.1/bin/node node scripts/eslint
src/platform/packages/shared/kbn-cps-utils/components/project_picker_content.tsx
src/platform/packages/shared/kbn-cps-utils/components/project_picker.tsx
x-pack/platform/plugins/private/canvas/public/components/datasource/datasource_component.js
che/ms-playwright/webkit-2272/minibrowser-gtk/MiniBrowser` (dns block)
> - `clients3.google.com`
> - Triggering command:
`/home/REDACTED/work/kibana/kibana/node_modules/@moonrepo/core-linux-x64-gnu/moon
/home/REDACTED/work/kibana/kibana/node_modules/@moonrepo/core-linux-x64-gnu/moon
run :build-webpack ldd 0.8.2` (dns block)
> - `detectportal.firefox.com`
> - Triggering command:
`/home/REDACTED/work/kibana/kibana/node_modules/@moonrepo/core-linux-x64-gnu/moon
/home/REDACTED/work/kibana/kibana/node_modules/@moonrepo/core-linux-x64-gnu/moon
run :build-webpack ldd 0.8.2` (dns block)
> - `google.com`
> - Triggering command:
`/home/REDACTED/work/kibana/kibana/node_modules/@moonrepo/core-linux-x64-gnu/moon
/home/REDACTED/work/kibana/kibana/node_modules/@moonrepo/core-linux-x64-gnu/moon
run :build-webpack ldd 0.8.2` (dns block)
> - `googlechromelabs.github.io`
> - Triggering command:
`/home/REDACTED/.nvm/versions/node/v24.14.1/bin/node
/home/REDACTED/.nvm/versions/node/v24.14.1/bin/node install.js` (dns
block)
> - `iojs.org`
> - Triggering command: `/usr/bin/curl curl -q --fail --compressed -L -s
REDACTED -o -` (dns block)
>
> If you need me to access, download, or install something from one of
these locations, you can either:
>
> - Configure [Actions setup
steps](https://gh.io/copilot/actions-setup-steps) to set up my
environment, which run before the firewall is enabled
> - Add the appropriate URLs or hosts to the custom allowlist in this
repository's [Copilot coding agent
settings](https://github.com/elastic/kibana/settings/copilot/coding_agent)
(admins only)
>
> </details>

---------

Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com>
Co-authored-by: alexwizp <20072247+alexwizp@users.noreply.github.com>
Co-authored-by: Alexey Antonov <alexwizp@gmail.com>
(cherry picked from commit 88407ef)