Add security remapping for holdings with sync protection (#692)

* Add security remapping support to holdings

- Introduced `provider_security` tracking for holdings with schema updates.
- Implemented security remap/reset workflows in `Holding` model and UI.
- Updated routes, controllers, and tests to support new functionality.
- Enhanced client-side interaction with Stimulus controller for remapping.

# Conflicts:
#	app/components/UI/account/activity_feed.html.erb
#	db/schema.rb

* Refactor "New transaction" to "New activity" across UI and tests

- Updated localized strings, button labels, and ARIA attributes.
- Improved error handling in holdings' current price display.
- Scoped fallback queries in `provider_import_adapter` to prevent overwrites.
- Added safeguard for offline securities in price fetching logic.

* Update security remapping to merge holdings on collision by deleting duplicates

- Removed error handling for collisions in `remap_security!`.
- Added logic to merge holdings by deleting duplicates on conflicting dates.
- Modified associated test to validate merging behavior.

* Update security remapping to merge holdings on collision by combining qty and amount

- Modified `remap_security!` to merge holdings by summing `qty` and `amount` on conflicting dates.
- Adjusted logic to calculate `price` for merged holdings.
- Updated test to validate new merge behavior.

* Improve DOM handling in Turbo redirect action & enhance holdings merge logic

- Updated Turbo's custom `redirect` action to use the "replace" option for cleaner DOM updates without clearing the cache.
- Enhanced holdings merge logic to calculate weighted average cost basis during security remapping, ensuring more accurate cost_basis updates.

* Track provider_security_id during security updates to support reset workflows

* Fix provider tracking: guard nil ticker lookups and preserve merge attrs

- Guard fallback 1b lookup when security.ticker is blank to avoid matching NULL tickers
- Preserve external_id, provider_security_id, account_provider_id during collision merge

* Fix schema.rb version after merge (includes tax_treatment migration)

* fix: Rename migration to run after schema version

The migration 20260117000001 was skipped in CI because it had a timestamp
earlier than the schema version (2026_01_17_200000). CI loads schema.rb
directly and only runs migrations with versions after the schema version.

Renamed to 20260119000001 so it runs correctly.

* Update schema: remove Coinbase tables, add new fields and indexes

* Update schema: add back `tax_treatment` field with default value "taxable"

* Improve Turbo redirect action: use "replace" to avoid form submission in history

* Lock merged holdings to prevent provider overwrites and fix activity feed template indentation

* Refactor holdings transfer logic: enforce currency checks during collisions and enhance merge handling

---------

Signed-off-by: Juan José Mata <juanjo.mata@gmail.com>
Co-authored-by: luckyPipewrench <luckypipewrench@proton.me>
Co-authored-by: Juan José Mata <juanjo.mata@gmail.com>

app/controllers/transactions_controller.rb

@@ -201,12 +201,17 @@ class TransactionsController < ApplicationController
       # Default activity label if not provided
       activity_label ||= is_sell ? "Sell" : "Buy"
 
-      # Create trade entry
+      # Create trade entry with note about conversion
+      conversion_note = t("transactions.convert_to_trade.conversion_note",
+        original_name: @entry.name,
+        original_date: I18n.l(@entry.date, format: :long))
+
       @entry.account.entries.create!(
         name: params[:trade_name] || Trade.build_name(is_sell ? "sell" : "buy", qty, security.ticker),
         date: @entry.date,
         amount: signed_amount,
         currency: @entry.currency,
+        notes: conversion_note,
         entryable: Trade.new(
           security: security,
           qty: signed_qty,