TB Perpetual calculator: tooltip copy, CTA rename, starting price (#2624)

* TB Perpetual calculator: tooltip copy, CTA rename, starting price

- Tooltips rewritten for Devices, Production/Development Instances, Add-ons,
  Edge Computing, Trendz Analytics, Offline Mode to be more specific and
  enterprise-oriented.
- "Calculate your pricing" CTA renamed to "Estimate my cost" on both the
  Self-Managed and Subscription plan cards.
- TB Perpetual hero: added "Starting from $4,999" price display and tightened
  subtitle copy.
- Added "License packages" section header to the Perpetual tab; adjusted
  header margin only when Perpetual tab is active.
- Edge Computing add-on toggle now defaults unchecked (was checked).
- Tooltip padding/line-height polished (`calculator.sass`).
- `generateAddOnsCards` scoped to `.add-ons[data-product-name]` so unrelated
  `.add-ons` containers on the page don't get clobbered.
- Restored `images/pricing/offline-add-on-icon.svg` used by the Offline Mode
  add-on card.

* Offline add-on icon: hardcode #2A7DEC to match other add-ons

The icon was authored with `currentColor` fills and inherited the text
color when embedded via `<img src>`, rendering black/grey against the
other two add-on icons' blue. Hardcode the fill to `#2A7DEC` to match
`edge-add-on-icon.svg` and `trendz-add-on-icon.svg`.

Author: rusikv

_includes/pricing/calculator.sass

@@ -298,12 +298,12 @@ $bg-white: #fff
             color: #fff
             text-align: left
             border-radius: 6px
-            padding: 5px
+            padding: 5px 10px
             font-size: 12px
             left: 19px
             top: -3px
             width: 250px
-            line-height: 24px
+            line-height: 18px
       .input-with-controls
         display: flex
         align-items: center
@@ -969,7 +969,7 @@ $bg-white: #fff
   right: 0
   bottom: 0
   background-color: rgba(0, 0, 0, 0.5)
-  z-index: 8888
+  z-index: 9999
   align-items: center
   justify-content: center
   &.visible
@@ -980,7 +980,7 @@ $bg-white: #fff
     padding: 8px
     border-radius: 24px
     background-color: #F7F9FC
-    max-height: min(912px, 100%)
+    height: min(912px, 100%)
     overflow: hidden
     .modal-body
       display: flex