community: add Skatt (Sweden) listing

[AlexanderBabel]

Listing

• Addon id: wealthfolio-skatt
• Repository: https://github.com/AlexanderBabel/wealthfolio-skatt
• Publisher (person or organisation responsible for the addon): AlexanderBabel

What changed

New community directory listing for Skatt (Sweden) — Swedish capital income tax
per calendar year for ISK, depå and crypto accounts, with a K4 avsnitt A CSV
export for Skatteverket. Includes the derived record from
pnpm derive:community and the regenerated community/README.md.

Derived clean: MIT licence, SDK 3.6.2 (current), no network permission so
userDataLeavesDevice is false, not-tax-advice notice from the tax tag.

Publisher attestation

I have read POLICIES.md and confirm:

• I am the publisher of this addon, or I am expressly authorised to act for
  the publisher. The author field names the publisher, not just my GitHub
  account.
• I have the rights to the name, description, logo, and screenshots I
  submitted, and I grant Wealthfolio permission to display them for this
  listing.
• The source repository is public and contains a licence file. (Wealthfolio
  reads the licence from the repository; a listing without a detectable one
  cannot be published.)
• Everything I declared is accurate — features, external services, and what
  happens to user data.
• There is no hidden data collection and no undisclosed remote code. My
  manifest declares every host the addon reaches, and anything reaching a
  service the manifest cannot show is declared in dataHandling with a
  privacyUrl.
• I am responsible for support, updates, security fixes, privacy compliance,
  licensing, and any commercial terms for this addon.
• The name and branding do not imply the addon is official, endorsed, or
  affiliated with Wealthfolio.
• I understand a listing is a link only: Wealthfolio does not host, build,
  audit, endorse, or support this addon, and may remove the listing at its
  discretion.

Metadata checklist

• File is at community/directory/<addon-id>/addon.store.json, and the
  directory name matches the id.
• commercialModel is set. Licence, compatibility, and standard notices are
  derived from your repository — do not fill those in.
• The repository has a licence file and a manifest.json at its root.
• The manifest declares sdkVersion 3.6 or newer.
• All URLs are HTTPS and resolve.
• pnpm validate:addons and pnpm generate pass locally with no diff.