chore: refactoring of notification banner

[svienot]

Description:

Refactor notification banner to make it a slot of PageFrameV2, such that the banner spans the whole window width.

Unrelated: Replace the placeholder icon for missing NFT image

[sonarqubecloud]

Quality Gate failed

Failed conditions
0.0% Coverage on New Code (required ≥ 80%)
7.7% Duplication on New Code (required ≤ 3%)

See analysis details on SonarQube Cloud

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	73.6%	23616 / 32084
🔵	Statements	73.6%	23616 / 32084
🔵	Functions	56.64%	921 / 1626
🔵	Branches	83.64%	4632 / 5538

File Coverage

File	Stmts	% Branch	% Funcs	% Lines	Uncovered Lines
Changed Files
src/components/page/Footer.vue	96.82%	70%	100%	96.82%	90, 92
src/components/page/PageFrameV2.vue	100%	100%	100%	100%
src/components/page/header/PageHeader.vue	97.14%	50%	0%	97.14%	1, 67
src/components/token/NftPreview.vue	90.47%	90.9%	0%	90.47%	96-98, 100
src/pages/AccountDetails.vue	41.48%	80.53%	0%	41.48%	1, 27, 29-30, 33-35, 37-42, 44, 47-55, 57-63, 67-69, 71-73, 75, 77, 80-82, 84-88, 90-92, 94-98, 100-102, 104-107, 109, 112, 114-115, 117-119, 121-126, 128, 130-132, 134-141, 143-150, 152-156, 158-162, 164-167, 169-173, 175-179, 181-182, 184-185, 187-193, 195-196, 198-199, 201-206, 208-210, 212-216, 218-220, 222, 225-229, 231-235, 237-241, 243, 245, 247, 249-251, 254-261, 264-282, 285-291, 293-295, 297-308, 310, 409-415, 418-419, 421, 461-462, 479-481
src/pages/AdminKeyDetails.vue	100%	71.42%	100%	100%
src/pages/BlockDetails.vue	94.39%	92.68%	0%	94.39%	168-170, 172-174
src/pages/ContractDetails.vue	98.37%	93.4%	0%	98.37%	38, 41, 44, 78
src/pages/NftDetails.vue	94.47%	85.96%	0%	94.47%	214, 246, 249-250, 255, 294-300
src/pages/NodeDetails.vue	98.37%	89.79%	100%	98.37%	1, 217, 236
src/pages/Staking.vue	100%	100%	100%	100%
src/pages/TokenDetails.vue	96.44%	96.72%	50%	96.44%	309, 342-347, 361-362
src/pages/TopicDetails.vue	96.99%	83.92%	100%	96.99%	38, 210-211, 215
src/pages/TransactionDetails.vue	98.27%	93.91%	0%	98.27%	234-236, 360, 430-431

Generated in workflow #1649

[ericleponner]

Looks good.