Add page-level share button with referral ID

[Copilot]

Section anchor links already append ?rid=<referralId> when copied, but there was no way to share the page URL itself with a referral ID attached.

Changes

• useSiteShell.js

  • Extracted addReferralIdToUrl(url) helper — eliminates duplicated referral ID injection logic
  • Extracted writeToClipboard(url, successMessage?) helper — shared by both copy functions
  • Added shareCurrentPage() — copies current page URL (no hash) with referral ID as ?rid=... if available; exposed in composable return

• PageNavigation.vue

  • Added a centered fa-solid fa-share-from-square button between prev/next arrows
  • Rendered only on content pages (v-if="shell.isContentPage")
  • Calls shareCurrentPage() on click with a "Share Page" tooltip

• styles.css

  • Added .tooltip-center for the share button tooltip positioning
  • Added border/padding reset for <button>.arrow-btn to match <a> sibling appearance

[Copilot]

Pull request overview

Adds a page-level “Share” action to copy the current page URL (without hash) with the referral ID (rid) appended when available, aligning page sharing behavior with existing section-link sharing.

Changes:

• Refactors clipboard/referral URL handling into shared helpers and introduces shareCurrentPage() in useSiteShell.js.
• Adds a centered share button to the page navigation UI (content pages only).
• Updates CSS to support centered tooltip positioning and button styling parity with existing nav arrows.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 2 comments.

File	Description
EssentialCSharp.Web/wwwroot/css/styles.css	Adds centered tooltip positioning and button reset styles for the new share control.
EssentialCSharp.Web/src/composables/useSiteShell.js	Extracts referral/clipboard helpers and adds shareCurrentPage() to copy the page URL with rid.
EssentialCSharp.Web/src/components/PageNavigation.vue	Introduces a share button between prev/next navigation arrows and wires it to shareCurrentPage().

Comments suppressed due to low confidence (1)

EssentialCSharp.Web/src/composables/useSiteShell.js:112

• The error snackbar message uses string interpolation on the raw error object, which often renders as [object DOMException] and isn’t helpful to users. Consider surfacing a friendlier message (e.g., error.message when available) while keeping the detailed object in console.error.

                (error) => {
                    console.error("Could not copy text to clipboard: ", error);
                    snackbarColor.value = "red";
                    snackbarMessage.value = `Error: Could not copy text to clipboard: ${error}`;
                }